While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

1

??Swainson???s hawk (Buteo swainsoni) has experienced population declines throughout much of its range and the most drastic decline has occurred in California. Once abundant throughout… (more)

Cahill, Kevin Paul

2014-01-01T23:59:59.000Z

2

Le grand astrophysicien S.Hawking, né le 08-01-1942 à Oxford, parle de "baby universes" et la gravitation et répond aux questions.

None

2011-04-25T23:59:59.000Z

3

Productivity, mortality, and response to disturbance of nesting Swainson's hawks on the Hanford Site

The objectives of this study were to characterize Swainson's hawk (Buteo swainson) use of the US Department of Energy (DOE) Hanford Site and to evaluate the potential for engineering and other human activities on the Hanford Site to negatively affect the nesting Swainson's hawk population. Activities associated with the Basalt Waste Isolation Project (BWIP) were used as the primary external stimuli in studying hawk responses to potential human disturbance. Parked and moving vehicles were the most common disturbance sources observed in Swainson's hawk territories. Hawks appeared to be sensitive to disturbance from pedestrians and slow-moving vehicles near nests. Novel stimuli were much more likely to evoke strong responses than were recurring events. Adult hawks reacted more frequently and vigorously than did juveniles. When disturbed, adult hawks usually flew toward the location of the disturbance; juvenile hawks usually flew away from disturbances. Human activity associated with BWIP may have had negative on one pair of nesting Swainson's hawks and may have precluded the use of an additional traditional nesting territory. Negative impacts to nesting Swainson's hawks from human activity could be minimized by confining activities to the non-nesting period or to distances greater than 2.2 km from nest sites. Tree groves and elevated perches, including utility poles, across the Hanford Site are probably critical to the success of nesting Swainson's hawks. Potential mitigation strategies associated with energy research and development activities on the Hanford Site could include provisions for maintenance and establishment of drought-tolerant trees and native vegetation. 22 refs., 5 figs., 3 tabs.

Poole, L.D.; Marr, N.V.; McCorquodale, S.M.

1988-03-01T23:59:59.000Z

4

Science Journals Connector (OSTI)

Publisher Summary The ferruginous hawk (Buteo regalis) is the largest soaring hawk in the United States with a maximum wingspan up to 1.32 meters (5 ft). The species is common to the grasslands and steppe areas of the western United States. The ferruginous hawk (Buteo regalis) was once common to the grassland areas of Washington State. The Washington State Department of Fish and Wildlife has identified nine territorial pairs that are using Bonneville Power Administration towers on the Hanford Reservation site in Central Washington. These pairs represent 18% of the active nesting population in 2002 of this threatened species as designated by the State. Ferruginous hawks did not range widely on the Reservation until specific transmission towers were introduced on the reservation in the 1970s. The nests are 2-3 ft. in diameter and are made of interwoven sagebrush stems in the lower part of the transmission tower body. To provide a better nesting site for the hawks, wood-nesting platforms were installed in the winter of 2003. These platforms are one-meter in diameter and are designed to prevent the nest from blowing out of the tower during high winds. A review of the nest platforms during the summer of 2003 indicated that at least one breeding pair that produced fledgling young occupied one nest. In 2004, with the assistance of ThermoSight, Inc, a remote camera was installed over the nest to observe and record the hawks during the nesting season.

William T. Erickson; James W. Watson; Bill Hubbard

2008-01-01T23:59:59.000Z

5

Thermality of the Hawking flux

Is the Hawking flux "thermal"? Unfortunately, the answer to this seemingly innocent question depends on a number of often unstated, but quite crucial, technical assumptions built into modern (mis-)interpretations of the word "thermal". The original 1850's notions of thermality --- based on classical thermodynamic reasoning applied to idealized "black bodies" or "lamp black surfaces" --- when supplemented by specific basic quantum ideas from the early 1900's, immediately led to the notion of the black-body spectrum, (the Planck-shaped spectrum), but "without" any specific assumptions or conclusions regarding correlations between the quanta. Many (not all) modern authors (often implicitly and unintentionally) add an extra, and quite unnecessary, assumption that there are no correlations in the black-body radiation; but such usage is profoundly ahistorical and dangerously misleading. Specifically, the Hawking flux from an evaporating black hole, (just like the radiation flux from a leaky furnace or a burning lump of coal), is only "approximately" Planck-shaped over a bounded frequency range. Standard physics (phase space and adiabaticity effects) explicitly bound the frequency range over which the Hawking flux is "approximately" Planck-shaped from both above and below --- the Hawking flux is certainly not exactly Planckian, and there is no compelling physics reason to assume the Hawking photons are uncorrelated.

Matt Visser

2014-09-27T23:59:59.000Z

6

Investigation of Operations of Hawk Pedestrian Treatment

functional forms are investigated in order to select an appropriate one that could more accurately model pedestrian delay. The minimum green time for vehicles, as an important variable in the HAWK pedestrian delay model and a peculiar element in HAWK...

Li, Siqi

2012-07-16T23:59:59.000Z

7

Hawking Emission and Black Hole Thermodynamics

A brief review of Hawking radiation and black hole thermodynamics is given, based largely upon hep-th/0409024.

Don N. Page

2006-12-18T23:59:59.000Z

8

Information-geometric aspects of Hawking radiation

This paper illustrates the resemblance between the information-geometric structures of probability spaces and that of the discrete spectrum for Hawking radiation. The information geometry gives rise to a reconstruction of the standard formalism of quantum mechanics, while the discrete spectrum of Hawking radiation contributes to the semiclassical unitary evolution of Hawking radiation. If more realistic models of Hawking radiation are chosen, the information-geometric structures of the probability space for Hawking radiation can be constructed from some physical considerations. The constructed quantum formalism is consistent with both the unitary evolution of Hawking radiation in the semiclassical picture and the topology change of fuzzy horizon. These aspects of Hawking radiation can be connected to some general convictions of quantum gravity such as holography. A comparison with fuzzball propasal shows the limiation and effectiveness of this construction. We conclude that the infromation-geometric aspects show some possible ways bridging the gap between semiclassical models and quantum gravity.

Xiao-Kan Guo

2014-10-04T23:59:59.000Z

9

c~ g, pe vhilc in g, gggg@fgg, sad g, ~ it is inter@edicts f eeo Plate II ) ihe eyes of the havhs esca to shiv e relatively longer eye then tlat other fo. u species vhioh exhihit s tondencgr tousrd flattening in an, enters posterior divest... c~ g, pe vhilc in g, gggg@fgg, sad g, ~ it is inter@edicts f eeo Plate II ) ihe eyes of the havhs esca to shiv e relatively longer eye then tlat other fo. u species vhioh exhihit s tondencgr tousrd flattening in an, enters posterior divest...

Lord, Rexford D

2012-06-07T23:59:59.000Z

10

Women @ Energy: Carol Hawk | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Carol Hawk Carol Hawk Women @ Energy: Carol Hawk March 13, 2013 - 5:05pm Addthis Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE) Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE) Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE). Her current duties include coordinating the CEDS program, which includes an industry-directed program, a research-directed program, the National SCADA test bed program, and an

11

Women @ Energy: Carol Hawk | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Carol Hawk Carol Hawk Women @ Energy: Carol Hawk March 13, 2013 - 5:05pm Addthis Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE) Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE) Dr. Carol Hawk is the Manager of the Cybersecurity for Energy Delivery Systems (CEDS) Program for the office of Electricity Delivery and Energy Reliability in the Department of Energy (DOE). Her current duties include coordinating the CEDS program, which includes an industry-directed program, a research-directed program, the National SCADA test bed program, and an

12

Hawking radiation on a falling lattice

Science Journals Connector (OSTI)

Scalar field theory on a lattice falling freely into a (1+1)-dimensional black hole is studied using both WKB and numerical approaches. The outgoing modes are shown to arise from incoming modes by a process analogous to a Bloch oscillation, with an admixture of negative frequency modes corresponding to the Hawking radiation. Numerical calculations show that the Hawking effect is reproduced to within 0.5% on a lattice whose proper spacing where the wavepacket turns around at the horizon is ?0.08 in units where the surface gravity is 1.

Ted Jacobson and David Mattingly

1999-12-21T23:59:59.000Z

13

Hawking radiation on a falling lattice

Scalar field theory on a lattice falling freely into a 1+1 dimensional black hole is studied using both WKB and numerical approaches. The outgoing modes are shown to arise from incoming modes by a process analogous to a Bloch oscillation, with an admixture of negative frequency modes corresponding to the Hawking radiation. Numerical calculations show that the Hawking effect is reproduced to within 0.5% on a lattice whose proper spacing where the wavepacket turns around at the horizon is $\\sim0.08$ in units where the surface gravity is 1.

Ted Jacobson; David Mattingly

2000-01-12T23:59:59.000Z

14

The Hawking-Unruh phenomenon on graphene

We find that, for a very specific shape of a monolayer graphene sample, a general relativistic-like description of a back-ground spacetime for graphene's conductivity electrons is very natural. The corresponding electronic local density of states is of finite temperature. This is a Hawking-Unruh effect that we propose to detect through an experiment with a Scanning Tunneling Microscope.

Alfredo Iorio; Gaetano Lambiase

2011-08-11T23:59:59.000Z

15

Science Journals Connector (OSTI)

The purpose of this Rapid Communication is to establish the basic properties—regularity at the horizon, time independence, and thermality—of the generalized Hartle-Hawking vacua defined in static spacetimes with a bifurcate Killing horizon admitting a regular Euclidean section. These states, for free or interacting fields, are defined by a Euclidean functional integral on half the Euclidean section. The emphasis is on generality, and the arguments are simple but formal.

Ted Jacobson

1994-11-15T23:59:59.000Z

16

Why Hawking Radiation Cannot Be Decoded

One of the great difficulties in the theory of black hole evaporation is that the most decisive phenomena tend to occur when the black hole is extremely hot: that is, when the physics is most poorly understood. Fortunately, a crucial step in the Harlow-Hayden approach to the firewall paradox, concerning the time available for decoding of Hawking radiation emanating from charged AdS black holes, can be made to work without relying on the unknown physics of black holes with extremely high temperatures; in fact, it relies on the properties of cold black holes. Here we clarify this surprising point. The approach is based on ideas borrowed from applications of the AdS/CFT correspondence to the quark-gluon plasma. Firewalls aside, our work presents a detailed analysis of the thermodynamics and evolution of evaporating charged AdS black holes with flat event horizons. We show that, in one way or another, these black holes are always eventually destroyed in a time which, while long by normal standards, is short relative to the decoding time of Hawking radiation.

Yen Chin Ong; Brett McInnes; Pisin Chen

2014-03-19T23:59:59.000Z

17

The self-screening Hawking atmosphere

A model is proposed in which the Hawking particles emitted by a black hole are treated as an envelope of matter that obeys an equation of state, and acts as a source in Einstein's equations. This is a crude but interesting way to accommodate for the back reaction. For large black holes, the solution can be given analytically, if the equation of state is $p=\\kappa\\rho$, with $0<\\kappa<1$. The solution exhibits a singularity at the origin. If we assume $N$ free particle types, we can use a Hartree-Fock procedure to compute the contribution of one such field to the entropy, and the result scales as expected as $1/N$. A slight mismatch is found that could be attributed to quantum corrections to Einstein's equations, but can also be made to disappear when $\\k$ is set equal to one. The case $\\kappa=1$ is further analysed.

G. 't Hooft

1997-08-06T23:59:59.000Z

18

Hawking spectrum and high frequency dispersion

Science Journals Connector (OSTI)

We study the spectrum of created particles in two-dimensional black hole geometries for a linear, Hermitian scalar field satisfying a Lorentz noninvariant field equation with higher spatial derivative terms that are suppressed by powers of a fundamental momentum scale k0. The preferred frame is the "free-fall frame" of the black hole. This model is a variation of Unruh's sonic black hole analogy. We find that there are two qualitatively different types of particle production in this model: a thermal Hawking flux generated by "mode conversion" at the black hole horizon, and a nonthermal spectrum generated via scattering off the background into negative free-fall frequency modes. This second process has nothing to do with black holes and does not occur for the ordinary wave equation because such modes do not propagate outside the horizon with positive Killing frequency. The horizon component of the radiation is astonishingly close to a perfect thermal spectrum: for the smoothest metric studied, with Hawking temperature TH?0.0008k0, agreement is of order (THk0)3 at frequency ?=TH, and agreement to order THk0 persists out to ?TH?45 where the thermal number flux is ?10-20. The flux from scattering dominates at large ? and becomes many orders of magnitude larger than the horizon component for metrics with a "kink," i.e., a region of high curvature localized on a static world line outside the horizon. This nonthermal flux amounts to roughly 10% of the total luminosity for the kinkier metrics considered. The flux exhibits oscillations as a function of frequency which can be explained by interference between the various contributions to the flux.

Steven Corley and Ted Jacobson

1996-07-15T23:59:59.000Z

19

Hawking radiation of Dirac particles from black strings

Hawking radiation has been studied as a phenomenon of quantum tunneling in different black holes. In this paper we extend this semi-classical approach to cylindrically symmetric black holes. Using the Hamilton-Jacobi method and WKB approximation we calculate the tunneling probabilities of incoming and outgoing Dirac particles from the event horizon and find the Hawking temperature of these black holes. We obtain results both for uncharged as well as charged particles.

Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

2011-08-01T23:59:59.000Z

20

Why Hawking Radiation Cannot Be Decoded

One of the great difficulties in the theory of black hole evaporation is that the most decisive phenomena tend to occur when the black hole is extremely hot: that is, when the physics is most poorly understood. Fortunately, a crucial step in the Harlow-Hayden approach to the firewall paradox, concerning the time available for decoding of Hawking radiation emanating from charged AdS black holes, can be made to work without relying on the unknown physics of black holes with extremely high temperatures; in fact, it relies on the properties of cold black holes. Here we clarify this surprising point. The approach is based on ideas borrowed from applications of the AdS/CFT correspondence to the quark-gluon plasma. Firewalls aside, our work presents a detailed analysis of the thermodynamics and evolution of evaporating charged AdS black holes with flat event horizons. We show that, in one way or another, these black holes are always eventually destroyed in a time which, while long by normal standards, is short relat...

Ong, Yen Chin; Chen, Pisin

2014-01-01T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

21

REMARKS ON THE BOX PROBLEM. Nets Hawk Katz, Elliot Krop, Mauro Maggioni

REMARKS ON THE BOX PROBLEM. Nets Hawk Katz, Elliot Krop, Mauro Maggioni Washington University Â§0 by a National Science Foundation grant Typeset by AMS-TEX 1 #12;2 NETS HAWK KATZ, ELLIOT KROP, MAURO MAGGIONI

Maggioni, Mauro

22

MHK Technologies/RED HAWK | Open Energy Information

RED HAWK RED HAWK < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage RED HAWK.jpg Technology Profile Primary Organization Natural Currents Energy Services Project(s) where this technology is utilized *MHK Projects/Avalon Tidal *MHK Projects/BW2 Tidal *MHK Projects/Cape Cod Tidal Energy Project *MHK Projects/Cape May Tidal Energy *MHK Projects/Cohansey River Tidal Energy *MHK Projects/Dorchester Maurice Tidal *MHK Projects/Fishers Island Tidal Energy Project *MHK Projects/Gastineau Channel Tidal *MHK Projects/Highlands Tidal Energy Project *MHK Projects/Killisnoo Tidal Energy *MHK Projects/Margate Tidal *MHK Projects/Maurice River Tidal *MHK Projects/Mohawk MHK Project *MHK Projects/Orient Point Tidal *MHK Projects/Rockaway Tidal Energy Plant

23

Hawking-Hayward quasi-local energy under conformal transformations

We derive a formula describing the transformation of the Hawking-Hayward quasi-local energy under a conformal rescaling of the spacetime metric. A known formula for the transformation of the Misner-Sharp-Hernandez mass is recovered as a special case.

Angus Prain; Vincenzo Vitagliano; Valerio Faraoni; Marianne Lapierre-Léonard

2015-01-13T23:59:59.000Z

24

Hawking-Hayward quasi-local energy under conformal transformations

We derive a formula describing the transformation of the Hawking-Hayward quasi-local energy under a conformal rescaling of the spacetime metric. A known formula for the transformation of the Misner-Sharp-Hernandez mass is recovered as a special case.

Prain, Angus; Faraoni, Valerio; Lapierre-Léonard, Marianne

2015-01-01T23:59:59.000Z

25

Fish Hawk, Florida: Energy Resources | Open Energy Information

Hawk, Florida: Energy Resources Hawk, Florida: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 27.850582Â°, -82.2109229Â° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":27.850582,"lon":-82.2109229,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

26

Black Hawk County, Iowa: Energy Resources | Open Energy Information

Hawk County, Iowa: Energy Resources Hawk County, Iowa: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 42.447804Â°, -92.3813621Â° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.447804,"lon":-92.3813621,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

27

Moving Mirrors, Black Holes, Hawking Radiation and All That

In this talk I show how to canonically quantize a massless scalar field in the background of a Schwarzschild black hole in Lema\\^itre coordinates and then present a simplified derivation of Hawking radiation based upon this procedure. The key result of quantization procedure is that the Hamiltonian of the system is explicitly time dependent and so problem is intrinsically non-static. From this it follows that, although a unitary time-development operator exists, it is not useful to talk about vacuum states; rather, one should focus attention on steady state phenomena such as the Hawking radiation. In order to clarify the approximations used to study this problem I begin by discussing the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Marvin Weinstein

2001-11-09T23:59:59.000Z

28

Moving Mirrors, Black Holes, Hawking Radiation and All That

In this talk I show how to canonically quantize a massless scalar field in the background of a Schwarzschild black hole in Lema\\^itre coordinates and then present a simplified derivation of Hawking radiation based upon this procedure. The key result of quantization procedure is that the Hamiltonian of the system is explicitly time dependent and so problem is intrinsically non-static. From this it follows that, although a unitary time-development operator exists, it is not useful to talk about vacuum states; rather, one should focus attention on steady state phenomena such as the Hawking radiation. In order to clarify the approximations used to study this problem I begin by discussing the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Weinstein, M A

2002-01-01T23:59:59.000Z

29

Moving Mirrors, Black Holes, Hawking Radiation and All That

In this talk I show how, in Lemaitre coordinates, one can canonically quantize a massless scalar field in the background of a Schwarzschild black hole and then show how this leads to a simplified derivation of Hawking radiation. The key result of the canonical quantization procedure is that the Hamiltonian of the system is explicitly time dependent, which immediately shows that the problem is intrinsically non-static and that, although a unitary time-development operator exists, it is not useful to talk about eigenstates. Rather, one should deal with the Heisenberg equations of motion and focus attention on steady state phenomena, such as the Hawking radiation. In order to clarify the procedure used to solve the Heisenberg equations I first discuss the related problem of the massless scalar field theory calculated in the presence of a moving mirror.

Weinstein, Marvin

2001-11-08T23:59:59.000Z

30

Knight Hawk adapts highwall mining for Southern Illinois

A few years ago while planning their first underground operation and trying to decide how to mine shallow seams, Knight Hawk purchased a 'Superior Highwall Miner' (SHM). Since then this small innovative company has been pioneering the use of highwall mining in a trenching application in for example the Illinois Basin. Highwall mining is very suitable for contour mining in Appalachia. The article discusses the recent improvements and the advantages of SHM mining systems. 3 photos.

Buchsbaum, L.

2007-10-15T23:59:59.000Z

31

Hawking radiation in the ghost condensate is nonthermal

We consider a Schwarzschild black hole immersed in a ghost condensate background. It is shown that the Hawking radiation in the quanta of small perturbations around this background is highly suppressed - in particular, it is not given by a thermal spectrum. This result is in accord with observations that such black holes can be used to violate the generalized second law of thermodynamics, and thus cannot have a standard entropy/area relation.

Feldstein, Brian [Department of Physics, Boston University, Boston, Massachusetts 02215 (United States)

2008-09-15T23:59:59.000Z

32

On the renormalization of the Gibbons-Hawking boundary term

Science Journals Connector (OSTI)

The bulk (Einstein-Hilbert) and boundary (Gibbons-Hawking) terms in the gravitational action are generally renormalized differently when integrating out quantum fluctuations. The former is affected by nonminimal couplings, while the latter is affected by boundary conditions. We use the heat kernel method to analyze this behavior for a nonminimally coupled scalar field, the Maxwell field, and the graviton field. Allowing for Robin boundary conditions, we examine in which cases the renormalization preserves the ratio of boundary and bulk terms required for the effective action to possess a stationary point. The implications for field theory and black hole entropy computations are discussed.

Ted Jacobson and Alejandro Satz

2014-03-17T23:59:59.000Z

33

Dirac Monopoles and Hawking radiation in Kottler spacetime

The natural extension of Schwarzschild metric to the case of nonzero cosmological constant $\\Lambda$ known as the Kottler metric is considered and it is discussed under what circumstances the given metric could describe the Schwarzschild black hole immersed in a medium with nonzero energy density. Under the latter situation such an object might carry topologically inequivalent configurations of various fields. The given possibility is analysed for complex scalar field and it is shown that the mentioned configurations might be tied with natural presence of Dirac monopoles on black hole under consideration. In turn, this could markedly modify the Hawking radiation process.

A. A. Bytsenko; Yu. P. Goncharov

2002-12-31T23:59:59.000Z

34

Hawking temperature of rotating charged black strings from tunneling

Thermal radiations from spherically symmetric black holes have been studied from the point of view of quantum tunneling. In this paper we extend this approach to study radiation of fermions from charged and rotating black strings. Using WKB approximation and Hamilton-Jacobi method we work out the tunneling probabilities of incoming and outgoing fermions and find the correct Hawking temperature for these objects. We show that in appropriate limits the results reduce to those for the uncharged and non-rotating black strings.

Ahmed, Jamil; Saifullah, K., E-mail: jamil_051@yahoo.com, E-mail: saifullah@qau.edu.pk [Department of Mathematics, Quaid-i-Azam University, Islamabad (Pakistan)

2011-11-01T23:59:59.000Z

35

Note on Hawking-Unruh effects in graphene

Beltrami-shaped graphene sheets have been recently proposed as analogs of curved spacetimes with Hawking-Unruh effects detected through typical condensed matter measurements involving scanning tunneling microscopes and spectroscopy. However, such deformed sheets, if ever fabricated, will contain large strain-induced pseudomagnetic fields with important guiding effects on the motion of the electrons in the conduction band. Besides, possible surface polariton and plasmon modes are known to be important players in the radiative heat transfer which takes place in the natural near-field nanoscale experimental conditions. Therefore, we suggest here that the latter class of experiments could shed light on phenomena related to the black hole membrane paradigm instead

Pisin Chen; H. C. Rosu

2012-05-17T23:59:59.000Z

36

Dielectric black holes induced by a refractive index perturbation and the Hawking effect

We consider a 4D model for photon production induced by a refractive index perturbation in a dielectric medium. We show that, in this model, we can infer the presence of a Hawking type effect. This prediction shows up both in the analogue Hawking framework, which is implemented in the pulse frame and relies on the peculiar properties of the effective geometry in which quantum fields propagate, as well as in the laboratory frame, through standard quantum field theory calculations. Effects of optical dispersion are also taken into account, and are shown to provide a limited energy bandwidth for the emission of Hawking radiation.

Belgiorno, F. [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, IT-20133 Milano (Italy); Cacciatori, S. L.; Gorini, V. [Department of Physics and Mathematics, Universita dell'Insubria, Via Valleggio 11, IT-22100 Como (Italy); INFN sezione di Milano, via Celoria 16, IT-20133 Milano (Italy); Ortenzi, G. [Dipartimento di Matematica e Applicazioni, Universita di Milano-Bicocca, Via Cozzi 53, IT-20125 Milano (Italy); Rizzi, L. [Department of Physics and Mathematics, Universita dell'Insubria, Via Valleggio 11, IT-22100 Como (Italy); Faccio, D. [School of Engineering and Physical Sciences, SUPA, Heriot-Watt University, Edinburgh, Scotland EH14 4AS (United Kingdom)

2011-01-15T23:59:59.000Z

37

Safety analysis of TCAS on Global Hawk using airspace encounter models

The U.S. Air Force's RQ-4 Global Hawk unmanned aerial vehicle (UAV) is a high altitude, long endurance aircraft used for surveillance and reconnaissance. Because of the potential for close proximity to manned aircraft in ...

Billingsley, Thomas B. (Thomas Boyd)

2006-01-01T23:59:59.000Z

38

Analogue Hawking Radiation in a dc-SQUID Array Transmission Line

We propose the use of a superconducting waveguide formed from an array of dc-SQUID's for investigating analogue Hawking radiation. Biasing the array with a space-time varying flux modifies the propagation velocity of the waveguide, leading to an effective metric with an horizon. Being a fundamentally quantum mechanical device, this setup allows for investigations of quantum effects such as back-reaction and analogue space-time fluctuations on the Hawking process.

P. D. Nation; M. P. Blencowe; A. J. Rimberg; E. Buks

2009-04-16T23:59:59.000Z

39

Thermodynamics and Hawking radiation of five-dimensional rotating charged Goedel black holes

We study the thermodynamics of Goedel-type rotating charged black holes in five-dimensional minimal supergravity. These black holes exhibit some peculiar features such as the presence of closed timelike curves and the absence of a globally spatial-like Cauchy surface. We explicitly compute their energies, angular momenta, and electric charges that are consistent with the first law of thermodynamics. Besides, we extend the covariant anomaly cancellation method, as well as the approach of the effective action, to derive their Hawking fluxes. Both the methods of the anomaly cancellation and the effective action give the same Hawking fluxes as those from the Planck distribution for blackbody radiation in the background of the charged rotating Goedel black holes. Our results further support that Hawking radiation is a quantum phenomenon arising at the event horizon.

Wu Shuangqing [College of Physical Science and Technology, HuaZhong Normal University, Wuhan, Hubei 430079 (China); Peng Junjin [College of Physical Science and Technology, HuaZhong Normal University, Wuhan, Hubei 430079 (China); College of Science, Wuhan Textile University, Wuhan, Hubei 430074 (China)

2011-02-15T23:59:59.000Z

40

Analogue gravity experiments make feasible the realisation of black hole spacetimes in a laboratory setting and the observational verification of Hawking radiation. Since such analogue systems are typically dominated by dispersion, efficient techniques for calculating the predicted Hawking spectrum in the presence of strong dispersion are required. In the preceding paper, an integral method in Fourier space is proposed for stationary $1+1$-dimensional backgrounds which are asymptotically symmetric. Here, this method is generalised to backgrounds which are different in the asymptotic regions to the left and right of the scattering region.

Scott Robertson

2014-03-27T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

41

Measuring Hawking Radiation of a Kerr-Newman Black Hole in a Superconducting Transmission Line

Applying a dimensional reduction technique and a coordinates transformation approach, we deduce the Kerr-Newman space-time into a Painlev\\'{e}-like form, and obtain its corresponding event horizon and the Hawking radiation temperature. We find that, the event horizon of a Kerr-Newman black hole can be simulated in a superconducting transmission line. Moreover, by running some numerical simulation, we confirm that the Hawking radiation of a Kerr-Newman Black Hole can be experimentally measured in a superconducting transmission line.

X. G. Lan; D. Y. Chen; L. F. Wei

2014-01-15T23:59:59.000Z

42

Probing the thermal character of analogue Hawking radiation for shallow water waves?

We study and numerically compute the scattering coefficients of shallow water waves blocked by a stationary counterflow. When the flow is transcritical, the coefficients closely follow Hawking's prediction according to which black holes should emit a thermal spectrum. We study how the spectrum deviates from thermality when reducing the maximal flow velocity, with a particular attention to subcritical flows since these have been recently used to test Hawking's prediction. For such flows, we show that the emission spectrum is strongly suppressed, and that its Planckian character is completely lost. For low frequencies, we also show that the scattering coefficients are dominated by elastic hydrodynamical channels. Our numerical results reproduce rather well the observations made by S. Weinfurtner {\\it et al.} in the Vancouver experiment. Nevertheless, we propose a new interpretation of what has been observed, as well as new experimental tests.

Florent Michel; Renaud Parentani

2014-09-15T23:59:59.000Z

43

The relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics

In Parikh and Wilczek's original works, the laws of black hole thermodynamics are not referred and it seems that there is no relation between Hawking radiation via tunnelling and the laws of black hole thermodynamics in their works. However, taking examples for the R-N black hole and the Kerr black hole, we find that they are correlated and even consistent if the tunnelling process is a reversible process.

Yapeng Hu; Jingyi Zhang; Zheng Zhao

2006-01-05T23:59:59.000Z

44

Hawking radiation has become experimentally testable thanks to the many analogue systems which mimic the effects of the event horizon on wave propagation. These systems are typically dominated by dispersion, and give rise to a numerically soluble and stable ODE only if the rest-frame dispersion relation $\\Omega^{2}(k)$ is a polynomial of relatively low degree. Here we present a new method for the calculation of wave scattering in a one-dimensional medium of arbitrary dispersion. It views the wave equation as an integral equation in Fourier space, which can be solved using standard and efficient numerical techniques.

Scott Robertson; Ulf Leonhardt

2014-03-27T23:59:59.000Z

45

Bekenstein-Hawking area law for black objects with conical singularities

We argue that, when working with the appropriate set of thermodynamical variables, the Bekenstein-Hawking law still holds for asymptotically flat black objects with conical singularities. The mass energy which enters the first law of thermodynamics does not, however, coincide with the Arnowitt-Deser-Misner mass; it differs from the latter by the energy associated with the conical singularity, as seen by an asymptotic, static observer. These statements are supported by a number of examples: the Bach-Weyl (double-Schwarzschild) solution, its dihole generalization in Einstein-Maxwell theory and the five-dimensional static black ring.

Herdeiro, Carlos [Centro de Fisica do Porto e Departamento de Fisica da Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal); Kleihaus, Burkhard; Kunz, Jutta; Radu, Eugen [Institut fuer Physik, Universitaet Oldenburg, Postfach 2503 D-26111 Oldenburg (Germany)

2010-03-15T23:59:59.000Z

46

Klein-Gordon equation and Hawking radiation in the dyon black hole with a cosmic string

Charged massive scalar particles are considered in the gravitational and electromagnetic field produced by a dyonic black hole with a cosmic string along the axis of symmetry. Exact solutions of both angular and radial parts of the covariant Klein-Gordon equation in this background are obtained, and are given in terms of the confluent Heun functions. We emphasize the role of the presence of the cosmic string in these solutions. From the radial solution, we obtain the exact wave solutions near the exterior horizon of the black hole, and discuss the Hawking radiation spectrum and the energy flux.

Vieira, H S; Silva, G V

2015-01-01T23:59:59.000Z

47

Influence of the back reaction of the Hawking radiation upon black hole quasinormal modes

Science Journals Connector (OSTI)

We consider the BTZ black hole surrounded by the conformal scalar field. Within general relativity, the resonant quasinormal (QN) modes dominate in the response of a black hole to external perturbations. At the same time, the metric of an evaporating black hole is affected by the Hawking radiation. We estimate the shift in the quasinormal spectrum of the BTZ black hole stipulated by the back reaction of the Hawking radiation. For the case of the (2+1)-dimensional black hole the corrected (by ??) metric is an exact solution [C. Martines and J. Zanelli, Phys. Rev. D 55, 3642 (1997)]. In addition, in this case quantum corrections come only from matter fields and not from graviton loops, that is, one can solve the problem of influence of the back reaction upon the QN ringing self-consistently. The dominant contribution to the corrections to the QNMs is simply a shift of ?2 proportional to -(?/M)3/2(4L2+M)?. It is negligible for large black holes but essential for small ones, giving rise to considerable increasing of the quality factor. Thus, the small evaporating black hole is expected to be a much better oscillator than a large one.

R. A. Konoplya

2004-08-18T23:59:59.000Z

48

The solutions of many issues, of the ongoing efforts to make deformed graphene a tabletop quantum field theory in curved spacetimes, are presented. A detailed explanation of the special features of curved spacetimes, originating from embedding portions of the Lobachevsky plane into $\\mathbf{R}^3$, is given, and the special role of coordinates for the physical realizations in graphene, is explicitly shown, in general, and for various examples. The Rindler spacetime is reobtained, with new important differences with respect to earlier results. The de Sitter spacetime naturally emerges, for the first time, paving the way to future applications in cosmology. The role of the BTZ black hole is also briefly addressed. The singular boundary of the pseudospheres, "Hilbert horizon", is seen to be closely related to event horizon of the Rindler, de Sitter, and BTZ kind. This gives new, and stronger, arguments for the Hawking phenomenon to take place. An important geometric parameter, $c$, overlooked in earlier work, takes here its place for physical applications, and it is shown to be related to graphene's lattice spacing, $\\ell$. It is shown that all surfaces of constant negative curvature, ${\\cal K} = -r^{-2}$, are unified, in the limit $c/r \\to 0$, where they are locally applicable to the Beltrami pseudosphere. This, and $c = \\ell$, allow us a) to have a phenomenological control on the reaching of the horizon; b) to use spacetimes different than Rindler for the Hawking phenomenon; c) to approach the generic surface of the family. An improved expression for the thermal LDOS is obtained. A non-thermal term for the total LDOS is found. It takes into account: a) the peculiarities of the graphene-based Rindler spacetime; b) the finiteness of a laboratory surface; c) the optimal use of the Minkowski quantum vacuum, through the choice of this Minkowski-static boundary.

Alfredo Iorio; Gaetano Lambiase

2014-12-15T23:59:59.000Z

49

Black holes as self-sustained quantum states, and Hawking radiation

We employ the recently proposed formalism of the "horizon wave-function" to investigate the emergence of a horizon in models of black holes as Bose-Einstein condensates of gravitons. We start from the Klein-Gordon equation for a massless scalar (toy graviton) field coupled to a static matter current. The (spherically symmetric) classical field reproduces the Newtonian potential generated by the matter source, and the corresponding quantum state is given by a coherent superposition of scalar modes with continuous occupation number. Assuming an attractive self-interaction that allows for bound states, one finds that (approximately) only one mode is allowed, and the system can be confined in a region of the size of the Schwarzschild radius. This radius is then shown to correspond to a proper horizon, by means of the horizon wave-function of the quantum system, with an uncertainty in size naturally related to the expected typical energy of Hawking modes. In particular, this uncertainty decreases for larger black hole mass (with larger number of light scalar quanta), in agreement with semiclassical expectations, a result which does not hold for a single very massive particle. We finally speculate that a phase transition should occur during the gravitational collapse of a star, ideally represented by a static matter current and Newtonian potential, that leads to a black hole, again ideally represented by the condensate of toy gravitons, and suggest an effective order parameter that could be used to investigate this transition.

Roberto Casadio; Andrea Giugno; Octavian Micu; Alessio Orlandi

2014-10-06T23:59:59.000Z

50

Observation of negative-frequency waves in a water tank: A classical analogue to the Hawking effect?

The conversion of positive-frequency waves into negative-frequency waves at the event horizon is the mechanism at the heart of the Hawking radiation of black holes. In black-hole analogues, horizons are formed for waves propagating in a medium against the current when and where the flow exceeds the wave velocity. We report on the first direct observation of negative-frequency waves converted from positive-frequency waves in a moving medium. The measured degree of mode conversion is significantly higher than expected from theory.

Germain Rousseaux; Christian Mathis; Philippe Maissa; Thomas G. Philbin; Ulf Leonhardt

2008-03-01T23:59:59.000Z

51

Onset and decay of the 1+1 Hawking-Unruh effect: what the derivative-coupling detector saw

We study an Unruh-DeWitt particle detector that is coupled to the proper time derivative of a real scalar field in 1+1 spacetime dimensions. Working within first-order perturbation theory, we cast the transition probability into a regulator-free form, and we show that the transition rate remains well defined in the limit of sharp switching. The detector is insensitive to the infrared ambiguity when the field becomes massless, and we verify explicitly the regularity of the massless limit for a static detector in Minkowski half-space. We then consider a massless field for two scenarios of interest for the Hawking-Unruh effect: an inertial detector in Minkowski spacetime with an exponentially receding mirror, and an inertial detector in $(1+1)$-dimensional Schwarzschild spacetime, in the Hartle-Hawking-Israel and Unruh vacua. In the mirror spacetime the transition rate traces the onset of an energy flux from the mirror, with the expected Planckian late time asymptotics. In the Schwarzschild spacetime the transition rate of a detector that falls in from infinity gradually loses thermality, diverging near the singularity proportionally to $r^{-3/2}$.

Benito A. Juárez-Aubry; Jorma Louko

2014-06-10T23:59:59.000Z

52

Onset and decay of the 1+1 Hawking-Unruh effect: what the derivative-coupling detector saw

We study an Unruh-DeWitt particle detector that is coupled to the proper time derivative of a real scalar field in 1+1 spacetime dimensions. Working within first-order perturbation theory, we cast the transition probability into a regulator-free form, and we show that the transition rate remains well defined in the limit of sharp switching. The detector is insensitive to the infrared ambiguity when the field becomes massless, and we verify explicitly the regularity of the massless limit for a static detector in Minkowski half-space. We then consider a massless field for two scenarios of interest for the Hawking-Unruh effect: an inertial detector in Minkowski spacetime with an exponentially receding mirror, and an inertial detector in $(1+1)$-dimensional Schwarzschild spacetime, in the Hartle-Hawking-Israel and Unruh vacua. In the mirror spacetime the transition rate traces the onset of an energy flux from the mirror, with the expected Planckian late time asymptotics. In the Schwarzschild spacetime the transit...

Juárez-Aubry, Benito A

2014-01-01T23:59:59.000Z

53

Effective spacetime and Hawking radiation from moving domain wall in thin film of 3He-A

An event horizon for "relativistic" fermionic quasiparticles can be constructed in a thin film of superfluid 3He-A. The quasiparticles see an effective "gravitational" field which is induced by a topological soliton of the order parameter. Within the soliton the "speed of light" crosses zero and changes sign. When the soliton moves, two planar event horizons (black hole and white hole) appear, with a curvature singularity between them. Aside from the singularity, the effective spacetime is incomplete at future and past boundaries, but the quasiparticles cannot escape there because the nonrelativistic corrections become important as the blueshift grows, yielding "superluminal" trajectories. The question of Hawking radiation from the moving soliton is discussed but not resolved.

T. A. Jacobson; G. E. Volovik

1998-11-04T23:59:59.000Z

54

Optimization in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman Black Holes

In this short report, we investigate the mutual information hidden in the Parikh-Wilczek tunneling model of Hawking radiation for Kerr-Newman black holes. By assuming the radiation as an optimization process, we discuss its effect on time evolution of rotating (charged and uncharged) black holes. For uncharged rotating black holes evaporating under the maximum mutual information optimization, their scale invariant rotation parameter $a_*=a/M$ is almost constant at the early stage but rapidly increase at the very last stage of the evaluation process. The value of rotation parameter at the final state of evaporation depends on the initial condition of the black hole. We also found that the presence of electric charge can cause the black holes lose their angular momentum more rapidly than they lose mass. The charged-rotating black holes asymptotically approach a state which is described by $a_*= 0$ and $Q/M = 1$.

Auttakit Chatrabhuti; Khem Upathambhakul

2014-03-17T23:59:59.000Z

55

COLLOQUIUM - HAWKING AUDITORIUM

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

particles, light particles and fragments will be reviewed. The variation of the nuclear binding energy with temperature and nucleonic density gives the opportunity to...

56

Carol Hawk | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Security for Energy Delivery Systems in the Office of Electricity Delivery and Energy Reliability. Most Recent Cyber Security Summer School: Lessons for the Modern Grid June 20...

57

Sarah EchoHawk | Department of Energy

Office of Environmental Management (EM)

(M.N.M.) degree from Regis University and earned her undergraduate degree in Political Science and Native American Studies from Metropolitan State University of Denver....

58

ISU College of Engineering/Black Hawk College Transfer Plan

Calculus II MATH 225 4 Phys 221 5 Classical Physics I PHYS 201 5 *May also transfer for AerE 160, CE 160. to Design GE 101 3 EM 274 AerE, AE, BSE, CE, ConE, IE, MatE, ME 3 Engineering Statics GE 201 3 EM 345 AerE, CE, ME 3 Dynamics GE 202 3 EM 324 AerE, AE, BSE, CE, ConE, MatE, ME 3 Mechanics of Materials GE 205 3

Hu, Hui

59

Hawking Radiation by Kerr Black Holes and Conformal Symmetry

The exponential blueshift associated with the event horizon of a black hole makes conformal symmetry play a fundamental role in accounting for its thermal properties. Using a derivation based on two-point functions, we show that the full spectrum of thermal radiation of scalar particles by Kerr black holes can be explicitly derived on the basis of a conformal symmetry arising in the wave equation near the horizon. The simplicity of our approach emphasizes the depth of the connection between conformal symmetry and black hole radiance.

Agullo, Ivan; Parker, Leonard [Physics Department, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States); Navarro-Salas, Jose [Departamento de Fisica Teorica and IFIC, Centro Mixto Universidad de Valencia-CSIC. Facultad de Fisica, Universidad de Valencia, Burjassot-46100, Valencia (Spain); Olmo, Gonzalo J. [Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid (Spain)

2010-11-19T23:59:59.000Z

60

Two Causal Analyses of the Black Hawk Shootdown during Operation Provide Comfort

- port [USA94], and we compare with Snook's Causal Copyright (c) 2003, Australian Computer Society, Inc were em- bedded in a complex command-and-control struc- ture. For this reason, along with the existence

Ladkin, Peter B.

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

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61

202 Western Birds 41:202230, 2010 SHORT-TAILED HAWKS NESTING IN THE SKY

, and southwestern Chihuahua commenced in the 1980s and since then have become increasingly numerous throughout the sky islands of Arizona, New Mexico, Sonora, and Chihuahua. In this report we summarize previously the exception of one bird in northwestern Chihuahua), have been of the light morph. The sky islands

Montana, University of

62

Gambling tourism and image marketing: an example from Black Hawk, Colorado

Many communities are now creatively competing to draw hics. visitors to their areas by taking a new turn for their tourism development. Legalized gaming has been introduced to some communities to act as a tool to attract more visitors and improve...

Yang, Xiaobing

2012-06-07T23:59:59.000Z

63

RED-TAILED HAWK POPULATIONS AND ECOLOGY IN EAST-CENTRAL WISCONSIN

this research plot entirely free of wood- chuck damage. Note that weeds must be kept from growing into the fence. Photo: A.T. Eaton Many animals use burrows started by woodchucks, including this red fox. Photo: A fences for woodchucks can be low enough that you usually do not need a gate. If you use non

64

NOAA/NASA Global Hawk Collaboration By Michael Black NOAA/AOML/HRD

scientists collaborated in the effort to conduct a first ever high-altitude flyover of a tropical cyclone were at their assigned stations in a specially designed operations room at the NASA Dryden Research, and scientific instrument status. They were prepared to staff, conduct, and monitor this flight for up to 18

65

Hawking-Unruh hadronization and strangeness production in high energy collisions

The interpretation of quark ($q$)- antiquark ($\\bar q$) pairs production and the sequential string breaking as tunneling through the event horizon of colour confinement leads to a thermal hadronic spectrum with a universal Unruh temperature, $T \\simeq 165$ Mev,related to the quark acceleration, $a$, by $T=a/2\\pi$. The resulting temperature depends on the quark mass and then on the content of the produced hadrons, causing a deviation from full equilibrium and hence a suppression of strange particle production in elementary collisions. In nucleus-nucleus collisions, where the quark density is much bigger, one has to introduce an average temperature (acceleration) which dilutes the quark mass effect and the strangeness suppression almost disappears.

Castorina, P

2015-01-01T23:59:59.000Z

66

Context in Enterprise Search and Delivery David Hawking Ccile Paris, Ross Wilkinson, Mingfang Wu

search brings its own typical context characteristics: users are mainly the employees, search tasks-related information. Document collection Â Enterprise searches are usually conducted in an intranet environment

Wu, Mingfang

67

Context in Enterprise Search and Delivery David Hawking, Ccile Paris, Ross Wilkinson, Mingfang Wu

its own typical context characteristics: users are mainly the employees, search tasks are usually-related information. Document collection Â Enterprise searches are usually conducted in an intranet environment

Hawking, David

68

Massive charged scalar field in the Kerr-Newman background II: Hawking radiation

We perform accurate calculations of the energy-, momentum-, and charge-emission rates of a charged scalar field in the background of the Kerr-Newman black hole at the range of parameters for which the effect is not negligibly small and, at the same time, the semiclassical regime is, at least marginally, valid. For black holes with charge below or not much higher than the charge accretion limit $Q \\sim \\mu M/e$ (where $e$ and $\\mu$ are the electron's mass and charge), the time between the consequent emitting of two charged particles is very large. For primordial black holes the transition between the increasing and decreasing of the ratio $Q/M$ occurs around the charge accretion limit. The rotation increases the intensity of radiation up to three orders, while the effect of the field's mass strongly suppresses the radiation.

R. A. Konoplya; A. Zhidenko

2014-04-03T23:59:59.000Z

69

Comment on ''Insensitivity of Hawking radiation to an invariant Planck-scale cutoff''

I point out that the cutoff introduced by Agulloet al.[I. Agullo, J. Navarro-Salas, G. J. Olmo, and ?>L. Parker, Phys. Rev. D 80, 047503 (2009)] has little impact on the trans-Planckian problem as it is usually understood; it excludes only a small fraction of the problematic modes.

Helfer, Adam D. [Department of Mathematics, University of Missouri, Columbia, Missouri 65211 (United States)

2010-05-15T23:59:59.000Z

70

Reply to 'Comment on 'Insensitivity of Hawking radiation to an invariant Planck-scale cutoff''

We clarify the relationship between the conclusions of the previous Comment of A. Helfer [A. Helfer, preceding Comment, Phys. Rev. D 81, 108501 (2010)] and that of our Brief Report [I. Agullo, J. Navarro-Salas, G. J. Olmo, and L. Parker, Phys. Rev. D 80, 047503 (2009).].

Agullo, Ivan; Parker, Leonard [Physics Department, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States); Navarro-Salas, Jose [Departamento de Fisica Teorica and IFIC, Centro Mixto Universidad de Valencia-CSIC, Facultad de Fisica, Universidad de Valencia, Burjassot-46100, Valencia (Spain); Olmo, Gonzalo J. [Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid (Spain); Physics Department, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201 (United States)

2010-05-15T23:59:59.000Z

71

Hawking Radiation Due to a Collapsing Star. II: Collapsing Shells in Two-Dimensional Space-Times

Science Journals Connector (OSTI)

......particle with respect to the Schwarzschild geometry of .5...the shell are portions of Schwarzschild geometries. The mass parameter...points S +' and S.' are mirror-images of Q. and Q+ with...same as that of the eternal Schwarzschild black hole except that there......

Kousuke Shizume; Shin Takagi

1989-04-01T23:59:59.000Z

72

An analysis of relations between the tunneling rate and the unified first law of thermodynamics at the trapping horizons of two kinds of spherically symmetric dynamical black holes is investigated. The first kind is the Vaidya-Bardeen black hole, the tunneling rate $\\Gamma \\sim e^{\\triangle S}$ can be obtained naturally from the unified first law at the apparent horizon, which holds the form $dE_{H}=TdS+WdV$. Another is the McVittie solution, the action of the radial null geodesic of the outgoing particles does not always has a pole at the apparent horizon, while the ingoing mode always has one. The solution of the ingoing mode of the radiation can be mathematically reduced to the case in the FRW universe smoothly. However as a black hole, the physical meaning is unclear and even puzzling.

Ke-Xia Jiang; San-Min Ke; Dan-Tao Peng

2011-05-03T23:59:59.000Z

73

Relations between the tunneling rate and the unified first law of thermodynamics at the apparent horizon of the FRW universe are investigated. The tunneling rate arises as a consequence of the unified first law of thermodynamics in such a dynamical system. The analysis shows obviously how the tunneling is intimately connected with the unified first law of thermodynamics through the principle of conservation of energy.

Ke-Xia Jiang; San-Min Ke; Dan-Tao Peng; Jun Feng

2008-12-16T23:59:59.000Z

74

Science Journals Connector (OSTI)

This study utilizes an ensemble Kalman filter (EnKF) to assess the impact of assimilating observations of Hurricane Karl from the High-altitude Imaging Wind and Rain Airborne Profiler (HIWRAP). HIWRAP is a new Doppler radar onboard the NASA Global ...

Jason A. Sippel; Fuqing Zhang; Yonghui Weng; Lin Tian; Gerald M. Heymsfield; Scott A. Braun

75

Science Journals Connector (OSTI)

Newly hatchedLeptinotarsa decemlineata larvae were less likely to initiate feeding onSolanum berthaultii than onS. tuberosum. Among larvae that fed there was no difference in the time to initiation of feeding; ho...

Jonathan J. Neal; Robert L. Plaisted; Ward M. Tingey

1991-10-01T23:59:59.000Z

76

from shape memory alloy (NiTi) coiled springs. An enhanced spring NiTi model describes the combination of micro-coil spring, we present a novel mesh-worm prototype that utilizes bio-inspired antagonistic structure alteration, NiTi can be restructured into coil springs. Chang et al.[1], discuss the numerous

Wood, Robert

77

Collider: 'God particle' theorist Peter Higgs attacks Stephen Hawking EARTH MOST VIEWED EARTH GALLERIES

Moczek, Armin P.

78

and flyspeck complex on apple Jean Carlson Batzer Maria Mercedes Diaz Arias Thomas C. Harrington Mark L: Sooty blotch and flyspeck (SBFS) is a complex of fungi that cause late-season blemishes of apple anamorph Zygophiala jamaicensis), caused flyspeck on apple. In the present study we compared morphology

Harrington, Thomas C.

79

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

selected team names: the C-Hawks and the Watt Watchers. Unlike traditional energy-efficiency programs that focus on the replacement of inefficient equipment such as...

80

E-Print Network 3.0 - amyotrophic diplegia related Sample Search...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Health: Stephen Hawking has atypical" ALS: 15; Amyotrophic Lateral Sclerosis. 15; Motor... . 15; General relativity good. 15; Put them together: a right proper mess. Two...

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81

Molecular architecture and functionalization of graphene surface...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Molecular architecture and functionalization of graphene surface; Synthesis and characterization Wednesday, November 12, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A...

82

E-Print Network 3.0 - advanced microscopy techniques Sample Search...

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microscopy techniques and their practice in relationship to materials structure characterization... of Microscopy", Edited by P.W. Hawkes and J.C.H. Spence, Springer, 2006 (An...

83

NETL F 451.1-1/1 Categorical Exclusion (CX) Designation Form

Broader source: Energy.gov (indexed) [DOE]

Materials Performance Division FE 0902 MPD 2011 Jeffrey A. Hawk Aug. 2011 - Aug. 2014 NETL: Albany, OR Analytical Physics - Transmission Electron Microscopy (TEM) To characterize...

84

NETL F 451.1/1-1, Categorical Exclusion Designation Form

Broader source: Energy.gov (indexed) [DOE]

Materials Develop. Div. FE ORDSMDD FY14-17 Jan. 2014 - Jan. 2017 Jeffrey A. Hawk NETL: Albany, OR Analytical Physics - Transmission Electron Microscopy (TEM)...

85

NETL Researcher Honored with 2013 Federal Laboratory Consortium...

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Jeffrey Hawk of the National Energy Technology Laboratory (NETL) has been awarded a Far West region Federal Laboratory Consortium (FLC) award for Outstanding Technology Development...

86

Science Driven Requirements for Seeded Soft X-ray Free Electron...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Wednesday, October 1, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Fulvio Parmigiani (Elettra Sincrotrone Trieste) Program Description Starting from the...

87

Long-Term Strategy for Environmental Stewardship and Sustainability

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Long-Term Strategy for Environmental Stewardship & Sustainability Hawks nesting Bike rider commutes to work at LANL A bobcat walking on LANL property Weather monitoring at LANL...

88

America and the Misshaping of a New World Order

Hawk) Battalion at Fort Bliss, Texas, he was a major when Ia clog in the works at Fort Bliss. I mean he used to piss

Gunn, Giles; Gutiérrez-Jones, Carl

2010-01-01T23:59:59.000Z

89

Resonant soft x-ray scattering: elemental/chemical specific probe...

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Resonant soft x-ray scattering: elementalchemical specific probe of reciprocal space and ordered structure Wednesday, October 15, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room...

90

Microsoft Word - moody_abstract

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

pm in Hawking Auditorium--Mitchel Institute Refreshments will be served at 3:30 pm FORENSIC RADIOCHEMISTRY Dr. Ken Moody Chemical Sciences Division, Lawrence Livermore National...

91

...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ......... . . . . . . ESS Game theory modeling: Hawks dashed line and Doves solid line. #12;Game Theory Kenneth Prestwich ...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ............. ......... . . . . . . ESS Game theory modeling: Hawks dashed line and Doves solid line. #12;c 1999 by Kenneth Prestwich. All are available on-line at: http: science.holycross.edu departments biology kprestwi behavior ESS ESS index frmset

Prestwich, Ken

92

Scalar emission in a rotating Gödel black hole

We study the absorption probability and Hawking radiation of the scalar field in the rotating G\\"{o}del black hole in minimal five-dimensional gauged supergravity. We find that G\\"{o}del parameter $j$ imprints in the greybody factor and Hawking radiation. It plays a different role from the angular momentum of the black hole in the Hawking radiation and super-radiance. These information can help us know more about rotating G\\"{o}del black holes in minimal five-dimensional gauged supergravity.

Songbai Chen; Bin Wang; Jiliang Jing

2008-08-23T23:59:59.000Z

93

.21 m/s] Â Davis Instruments Wind Speed Meter 0271 Visualization Â He Bubbles and Smoke #12;Results, Wrist AngleResults, Wrist Angle Red-tailed Hawk Minimal effect Jumps are due to exposure of covert

Peraire, Jaime

94

A Computational Framework for Determination and Exploitation of

from Wide-Area Persistent Surveillance Imagery Project Leads Jon Protz, PhD, Duke University Sam) such as the Predator, Global Hawk, Reaper, and Liberty, although a variety of different platforms-- including

McShea, Daniel W.

95

Autonomous Systems Design A Human Centric Paradox

Harrier VSTOL recovery to ship Â· Global Hawk strategic surveillance UAV Â· Rosetta comet interception-recovery to a Ship Â· Autonomous recovery and landing on a ship Â· Pilot initiates and gives permission to proceed

Cummings, Mary "Missy"

96

SiteEnvironmentalReport BROOKHAVENNATIONALLABORATORY

species are known to nest on site. The Red-tailed hawk, a bird of prey, is protected by the Migratory Bird Treaty Act. Chapter 6 of this report discusses habitat management and protection efforts

97

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Presentation overview 1. CPL: what it is, what it does 1. CPL, CLASIC, and that NASA A-Train 1. UAV-CPL on Global Hawk next-generation airborne science 4. Where to next?...

98

E-Print Network 3.0 - american raptor american Sample Search...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1 Proceedings of the South Dakota Academy of Science,Vol. 76 (1997) 113 EFFECTS OF WIND TURBINES ON NESTING Summary: -tailed hawks, northern harri- ers, and American kestrels...

99

Broader source: Energy.gov [DOE]

An article by OE’s Carol Hawk and Akhlesh Kaushiva in The Electricity Journal discusses cybersecurity for the power grid and how DOE and the energy sector are partnering to keep the smart grid reliable and secure.

100

E-Print Network 3.0 - aged non-human primates Sample Search Results

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

on populations of wild primates has been difficult Summary: - hawk eagle prey. Age and sex classes of prey We ascertained the age classes of primate prey in nearly... to the...

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

101

E-Print Network 3.0 - aging non-human primate Sample Search Results

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

on populations of wild primates has been difficult Summary: - hawk eagle prey. Age and sex classes of prey We ascertained the age classes of primate prey in nearly... to the...

102

The Weyl curvature tensor, the Cotton-York tensor and gravitational waves

We investigate the link between the Cotton-York tensor and its link to gravitational waves. Our study is carried out in the language of the congruence approach pioneered by Hawking and Ellis[2].

Osano, Bob

2013-01-01T23:59:59.000Z

103

Cybersecurity and the Smarter Grid (2014)

Broader source: Energy.gov [DOE]

An article by OE’s Carol Hawk and Akhlesh Kaushiva in The Electricity Journal discusses cybersecurity for the power grid and how DOE and the energy sector are partnering to keep the smart grid reliable and secure.

104

A brief commentary on black hole entropy

It is commonplace, in the literature, to find that the Bekenstein-Hawking entropy has been endowed with having an explicit statistical interpretation. In the following essay, we discuss why such a viewpoint warrants a certain degree of caution.

A. J. M. Medved

2004-10-18T23:59:59.000Z

105

Science Journals Connector (OSTI)

High frequency dispersion does not alter the low frequency spectrum of Hawking radiation from a single black hole horizon, whether the dispersion entails subluminal or superluminal group velocities. We show here that in the presence of an inner horizon as well as an outer horizon the superluminal case differs dramatically however. The negative energy partners of Hawking quanta return to the outer horizon and stimulate more Hawking radiation if the field is bosonic or suppress it if the field is fermionic. This process leads to exponential growth or damping of the radiated flux and correlations among the quanta emitted at different times, unlike in the usual Hawking effect. These phenomena may be observable in condensed matter black hole analogues that exhibit “superluminal” dispersion.

Steven Corley and Ted Jacobson

1999-05-17T23:59:59.000Z

106

City of Cuero Site Analysis and Redevelopment Recommendations

such as hawks, deer, and ibis. Numerous bird species fly over Cuero during fall and spring migrations, making Cuero an ideal location for bird-watching ecotourism. Other wildlife viewing, hunting, and fishing opportunities can be found in the nearby...

Bright, Elise; Galindo, Dan; Briggs, Jared; Hill, Kelli; Lehert, Angie; Miller, Kristi; Newcomer, Erin; Nguyen, Truong; Proctor, Nathanael; Shrestha, Anushma; Thomas, John Earl; Webster, Abigail; Zhou, Lijing

2009-01-01T23:59:59.000Z

107

AACR Celebrates 50 Years of Tobacco Research and Policy

Science Journals Connector (OSTI)

...Minneapolis, MN Ernest Hawk, MD, MPH The University of Texas MD Anderson Cancer Center, Houston, TX Waun Ki Hong, MD, DMSc (Hon.) The University of Texas MD Anderson Cancer Center, Houston, TX Fadlo R. Khuri, MD Winship Cancer Institute, Emory...

Roy S. Herbst; Jennifer A. Hobin; Ellen R. Gritz

2014-04-01T23:59:59.000Z

108

Computational imaging for 3D phase and coherence retrieval |...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Computational imaging for 3D phase and coherence retrieval Wednesday, December 10, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Laura Waller (UC Berkeley) Program...

109

Femtosecond-scale x-ray FEL diagnostics with an X-band transverse...

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Femtosecond-scale x-ray FEL diagnostics with an X-band transverse deflector Wednesday, October 22, 2014 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Tim Maxwell,...

110

Fermilab | Science | Inquiring Minds | Questions About Physics

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

out of the horizon, it can get away from the black hole because it always travels at the speed of light. Will: Or are you suggesting that the Hawking radiation itself is likely to...

111

Thermodynamics of the Schwarzschild-de Sitter black hole: Thermal stability of the Nariai black hole

We study the thermodynamics of the Schwarzschild-de Sitter black hole in five dimensions by introducing two temperatures based on the standard and Bousso-Hawking normalizations. We use the first-law of thermodynamics to derive thermodynamic quantities. The two temperatures indicate that the Nariai black hole is thermodynamically unstable. However, it seems that black hole thermodynamics favors the standard normalization and does not favor the Bousso-Hawking normalization.

Myung, Yun Soo [Institute of Basic Science and School of Computer Aided Science Inje University, Gimhae 621-749 (Korea, Republic of)

2008-05-15T23:59:59.000Z

112

Thermodynamics of Schwarzschild-de Sitter black hole: thermal stability of Nariai black hole

We study thermodynamics of the Schwarzschild-de Sitter black hole in five dimensions by introducing two temperatures based on the standard and Bousso-Hawking normalizations. We use the first-law of thermodynamics to derive thermodynamic quantities. The two temperatures indicate that the Nariai black hole is thermodynamically unstable. However, it seems that black hole thermodynamics favors the standard normalization, and does not favor the Bousso-Hawking normalization.

Yun Soo Myung

2007-12-20T23:59:59.000Z

113

Absorption cross section of RN black hole

The behavior of a charged scalar field in the RN black hole space time is studied using WKB approximation. In the present work it is assumed that matter waves can get reflected from the event horizon. Using this effect, the Hawking temperature and the absorption cross section for RN black hole placed in a charged scalar field are calculated. The absorption cross section $\\sigma _{abs}$ is found to be inversely proportional to square of the Hawking temperature of the black hole.

Sini R.; V. C. Kuriakose

2007-08-23T23:59:59.000Z

114

Static detectors and circular-geodesic detectors on the Schwarzschild black hole

We examine the response of an Unruh-DeWitt particle detector coupled to a massless scalar field on the (3+1)-dimensional Schwarzschild spacetime, in the Boulware, Hartle-Hawking and Unruh states, for static detectors and detectors on circular geodesics, by primarily numerical methods. For the static detector, the response in the Hartle-Hawking state exhibits the known thermality at the local Hawking temperature, and the response in the Unruh state is thermal at the local Hawking temperature in the limit of a large detector energy gap. For the circular-geodesic detector, we find evidence of thermality in the limit of a large energy gap for the Hartle-Hawking and Unruh states, at a temperature that exceeds the Doppler-shifted local Hawing temperature. Detailed quantitative comparisons between the three states are given. The response in the Hartle-Hawking state is compared with the response in the Minkowski vacuum and in the Minkowski thermal state for the corresponding Rindler, drifted Rindler, and circularly accelerated trajectories. The analysis takes place within first-order perturbation theory and relies in an essential way on stationarity.

Lee Hodgkinson; Jorma Louko; Adrian C. Ottewill

2014-05-05T23:59:59.000Z

115

Black hole and baby universe in a thin film of 3He-A

Condensed matter black hole analogues may provide guidance in grappling with difficult questions about the role of short distance physics in the Hawking effect. These questions bear on the very existence of Hawking radiation, the correlations it may or may not carry, the nature of black hole entropy, and the possible loss of information when a black hole evaporates. We describe a model of black hole formation and evaporation and the loss of information to a disconnected universe in a thin film of 3He-A, and we explain why the existence of Hawking radiation has not yet been demonstrated in this model. [We would like this article to be accessible to researchers in both condensed matter and gravitational physics, hence we include more than the usual amount of introductory material.

Ted Jacobson; Tatsuhiko Koike

2002-05-08T23:59:59.000Z

116

The information paradox: A pedagogical introduction

The black hole information paradox is a very poorly understood problem. It is often believed that Hawking's argument is not precisely formulated, and a more careful accounting of naturally occurring quantum corrections will allow the radiation process to become unitary. We show that such is not the case, by proving that small corrections to the leading order Hawking computation cannot remove the entanglement between the radiation and the hole. We formulate Hawking's argument as a `theorem': assuming `traditional' physics at the horizon and usual assumptions of locality we will be forced into mixed states or remnants. We also argue that one cannot explain away the problem by invoking AdS/CFT duality. We conclude with recent results on the quantum physics of black holes which show the the interior of black holes have a `fuzzball' structure. This nontrivial structure of microstates resolves the information paradox, and gives a qualitative picture of how classical intuition can break down in black hole physics.

Samir D. Mathur

2011-01-25T23:59:59.000Z

117

The coordinate coherent states approach revisited

We revisit the coordinate coherent states approach through two different quantization procedures in the quantum field theory on the noncommutative Minkowski plane. The first procedure, which is based on the normal commutation relation between an annihilation and creation operators, deduces that a point mass can be described by a Gaussian function instead of the usual Dirac delta function. However, we argue this specific quantization by adopting the canonical one (based on the canonical commutation relation between a field and its conjugate momentum) and show that a point mass should still be described by the Dirac delta function, which implies that the concept of point particles is still valid when we deal with the noncommutativity by following the coordinate coherent states approach. In order to investigate the dependence on quantization procedures, we apply the two quantization procedures to the Unruh effect and Hawking radiation and find that they give rise to significantly different results. Under the first quantization procedure, the Unruh temperature and Unruh spectrum are not deformed by noncommutativity, but the Hawking temperature is deformed by noncommutativity while the radiation specturm is untack. However, under the second quantization procedure, the Unruh temperature and Hawking temperature are untack but the both spectra are modified by an effective greybody (deformed) factor. - Highlights: Black-Right-Pointing-Pointer Suggest a canonical quantization in the coordinate coherent states approach. Black-Right-Pointing-Pointer Prove the validity of the concept of point particles. Black-Right-Pointing-Pointer Apply the canonical quantization to the Unruh effect and Hawking radiation. Black-Right-Pointing-Pointer Find no deformations in the Unruh temperature and Hawking temperature. Black-Right-Pointing-Pointer Provide the modified spectra of the Unruh effect and Hawking radiation.

Miao, Yan-Gang, E-mail: miaoyg@nankai.edu.cn; Zhang, Shao-Jun, E-mail: sjzhang@mail.nankai.edu.cn

2013-02-15T23:59:59.000Z

118

Broader source: Energy.gov (indexed) [DOE]

Carol Hawk Carol Hawk Program Manager U.S. Department of Energy Cybersecurity for Energy Delivery Systems July 20, 2010 2 Roadmap Vision In 10 years, control systems for critical applications will be designed, installed, operated, and maintained to survive an intentional cyber assault with no loss of critical function. * Published in January 2006 * Energy Sector's synthesis of critical control system security challenges, R&D needs, and implementation milestones * Provides strategic framework to - align activities to sector needs - coordinate public and private programs - stimulate investments in control systems security Roadmap - Framework for Public-Private Collaboration Roadmap Strategies Develop and Integrate Protective Measures

119

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

65 65 Annual Review FY2012 Name Affiliation Title Gemmen, Randall NETL Division Director (DD) Hawk, Jeffrey NETL Materials Research Engineer Holcomb, Gordon NETL Materials Research Engineer Jablonski, Paul NETL Metallurgist Robey, Edward URS Contractor Project Lead Argetsinger, Edward URS Engineering Technician Burkey, Edward URS Engineering Technician Name Affiliation Role University Project Title Seetharaman, Sridhar Zhu, Jingxi CMU PI Grad Student Fundamental Examination of Deposit Compositions Associated with Fireside Corrosion Meier, Gerald Yanar, Nazik Lutz, Michael Pitt PI Co-PI Grad Student Fundamental Examination of Deposit Compositions Associated with Fireside Corrosion ADVANCED COMBUSTION NETL Federal Project Manager: Randy Gemmen NETL Team Technical Coordinator: Jeff Hawk Appendix A:

120

How red is a quantum black hole?

Radiating black holes pose a number of puzzles for semiclassical and quantum gravity. These include the transplanckian problem -- the nearly infinite energies of Hawking particles created near the horizon, and the final state of evaporation. A definitive resolution of these questions likely requires robust inputs from quantum gravity. We argue that one such input is a quantum bound on curvature. We show how this leads to an upper limit on the redshift of a Hawking emitted particle, to a maximum temperature for a black hole, and to the prediction of a Planck scale remnant.

Viqar Husain; Oliver Winkler

2005-05-30T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

121

Semiclassical decay of near-extremal black holes

Science Journals Connector (OSTI)

The decay of a near-extremal black hole down to the extremal state is studied in the background field approximation to determine the fate of injected matter and Hawking pairs. By examining the behavior of light rays and solutions to the wave equation it is concluded that the singularity at the origin is irrelevant. Furthermore, there is most likely an instability of the event horizon arising from the accumulation of injected matter and Hawking partners there. The possible role of this instability in reconciling the D-brane and black hole pictures of the decay process is discussed.

Ted Jacobson

1998-04-15T23:59:59.000Z

122

Conformal Invariance of Black Hole Temperature

It is shown that the surface gravity and temperature of a stationary black hole are invariant under conformal transformations of the metric that are the identity at infinity. More precisely, we find a conformal invariant definition of the surface gravity of a conformal Killing horizon that agrees with the usual definition(s) for a true Killing horizon and is proportional to the temperature as defined by Hawking radiation. This result is reconciled with the intimate relation between the trace anomaly and the Hawking effect, despite the {\\it non}invariance of the trace anomaly under conformal transformations.

Ted Jacobson; Gungwon Kang

1993-07-06T23:59:59.000Z

123

Anniversary 3 Annual Report 2008–2009 An incunable from the first Italian press: the editio princeps of Lactantius, printed in Subiaco in October 1465. University officials survey weights and measures and burn those found to be false, as depicted in a... , poet (b. 1941) (presented by Mr Mole) n Papers of Peter W. Hawkes, principally concerning electron microscopy (presented by Dr Hawkes) n Notes taken by F.A. Fuggle during Louis Leakey’s excavation at Rickson’s Pit, Swanscombe, Kent, 1934...

Cambridge University Library

2013-09-26T23:59:59.000Z

124

Tunnelling of relativistic particles from new type black hole in new massive gravity

In the framework of the three dimensional New Massive Gravity theory introduced by Bergshoeff, Hohm and Townsend, we analyze the behavior of relativistic spin-1/2 and spin-0 particles in the New-type Black Hole backgroud, solution of the New Massive Gravity.We solve Dirac equation for spin-1/2 and Klein-Gordon equation for spin-0. Using Hamilton-Jacobi method, we discuss tunnelling probability and Hawking temperature of the spin-1/2 and spin-0 particles for the black hole. We observe that the tunnelling probability and Hawking temperature are same for the spin-1/2 and spin-0.

Gecim, Ganim; Sucu, Yusuf, E-mail: ganimgecim@akdeniz.edu.tr, E-mail: ysucu@akdeniz.edu.tr [Department of Physics, Akdeniz University, Antalya (Turkey)

2013-02-01T23:59:59.000Z

125

Some remarks on black hole thermodynamics

Two thermodynamic "paradoxes" of black hole physics are re-examined. The first is that there is a thermal instability involving two coupled blackbody cavities containing two black holes, and second is that a classical black hole can swallow up entropy in the form of ambient blackbody photons without increasing its mass. The resolution of the second paradox by Bekenstein and by Hawking is re-visited. The link between Hawking radiation and Wigner's superluminal tunneling time is discussed using two equivalent Feynman diagrams, and Feynman's re-interpretation principle.

R. Y. Chiao

2010-12-27T23:59:59.000Z

126

in the faculty as Solow was 110% hawk, Arrow was a dove; interesting as both sons of immigrants and these are usually patriots, but Ken thought it an immoral war; people like Hahn and even Meade were inclined to be hawks, partly because Robinson was a raving... player in the New London Orchestra which was conducted by Alex Sherman; as I had no orchestral experience and asked for an audition and he liked me; the piece we played was Mozart's great C minor concerto which has incredibly difficult wind parts...

Macfarlane, Alan

2014-12-12T23:59:59.000Z

127

College and University Presidents' Climate Commitment for reducing carbon emissions, among other things- ration and construction, a HAWK (High-intensity Activated crossWalK) beacon was activated on North Avenue. This photo was taken inside the pavilion last week. For more information about the project, visit www

Goodisman, Michael

128

Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 1)

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 1 are the pattern and configuration files for the pattern showed in Figure 2a in the paper.

Seibert, M. Marvin; Ekeberg, Tomas; Maia, Filipe R.N.C.

129

Single mimivirus particles intercepted and imaged with an X-ray laser (CXIDB ID 2)

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

These are the files used to reconstruct the images in the paper "Single Mimivirus particles intercepted and imaged with an X-ray laser". Besides the diffracted intensities, the Hawk configuration files used for the reconstructions are also provided. The files from CXIDB ID 2 are the pattern and configuration files for the pattern showed in Figure 2b in the paper.

Seibert, M. Marvin; Ekeberg, Tomas

130

Science Journals Connector (OSTI)

... eheu! fugaces) many volumes on many aspects of sport and natural history. Among his recreations are outings on the moor, the hill, and into the quiet byways of the ... he perhaps loves best of all, “a cast of hawks.” Another form of “recreation” has been—metaphorically speaking—“finding a hare in the library and hunting it through ...

F.

1906-05-24T23:59:59.000Z

131

SCHOOL OF FORESTRY UNIVERSITY OF CANTERBURY

Sc Aitcheson, D. Public use of Naseby Forest: a methodology for estimating a non-market value of user benefits Valley, Hawkes Bay, BForSc Alexander, G.H. A methodology for forecasting forest harvest machinery demands of Piper methysticum, MForSc report Amatus, P. Plant enumeration survey on Nissan Island, North Solomons

Hickman, Mark

132

Quality and relevance of domain-specific search: a case study in mental health

Department of Computer Science CSIT Building, ANU Canberra, ACT 0200, Australia thanh.tang@cs.anu.edu.au Nick Craswell and David Hawking CSIRO ICT Centre CSIT Building, ANU Canberra, ACT 2601, Australia nick Google, in order to better understand the relative merits of the two types of engine. It investigates

Hawking, David

133

Science Journals Connector (OSTI)

...CS , Young H, O'Reilly SM, et al. Early evaluation...TZ , Turkington TG, Hawk TC Coleman RE. PET and brain...0 Antineoplastic Agents 0 Radiopharmaceuticals 154-93-8 Carmustine 50-02-2...Positron-Emission Tomography Radiopharmaceuticals diagnostic use Rats

Craig J. Galbán; Mahaveer S. Bhojani; Kuei C. Lee; Charles R. Meyer; Marcian E. Van Dort; Kyle K. Kuszpit; Robert A. Koeppe; Rajesh Ranga; Bradford A. Moffat; Timothy D. Johnson; Thomas L. Chenevert; Alnawaz Rehemtulla; and Brian D. Ross

2010-03-01T23:59:59.000Z

134

Effects of Airline Strategies on Airline Operations and Infrastructure Utilization

the results of a multi-agent simulation of the evolution of Airline Operation Center (AOC) decision. The results show the emergence of hawk and dove alliances in AOC strategies. In some cases, these strategies (AOC) decision-making for trans-continental route selection when demand for the routes is in excess

135

Engineering a multi-purpose test collection for Web retrieval experiments

quantities of dark matter (Bailey, Craswell, & Hawking, 2000) due to Web page access restrictions, to lackEngineering a multi-purpose test collection for Web retrieval experiments Peter Bailey a,*, Nick methods for the Web has been restricted by the lack of a test collection capable of supporting experiments

Tomkins, Andrew

136

Proceedings of the South Dakota Academy of Science,Vol. 76 (1997) 113 EFFECTS OF WIND TURBINES influenced by the presence of wind turbines. Red-tailed and Swainson's hawks, American kestrels, and northern resources such as wind- power have received strong public support, impacts of wind turbines on avian

137

N e w s F o r & A b o u t U n i v e r s i t y o f F l o r i d a

of a seagull or a hawk." Powered by tiny electric motors and equipped with marble-sized video cameras, the UF engineering doctoral student Mujahid Abdulrahim fine tunes one of the micro air vehicles he helped design, is part of a UF team building "micro air vehicles" with wingspans of less than six inches. "We

Pilyugin, Sergei S.

138

Astronomy & Astrophysics manuscript no. HUGSv11 c ESO 2014 September 26, 2014

Astronomy & Astrophysics manuscript no. HUGSv11 c ESO 2014 September 26, 2014 The Hawk-I UDS for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJ, UK 3 Department of Physics and Astronomy, Sonoma State University, Rohnert Park, CA, SA 4 Max-Planck-Institut fur extraterrestrische Physik

Faraon, Andrei

139

Emission of scalar particles from cylindrical black holes

We study quantum tunneling of scalar particles from black strings. For this purpose we apply WKB approximation and Hamilton-Jacobi method to solve the Klein-Gordon equation for outgoing trajectories. We find the tunneling probability of outgoing charged and uncharged scalars from the event horizon of black strings, and hence the Hawking temperature for these black configurations.

H. Gohar; K. Saifullah

2011-09-27T23:59:59.000Z

140

Science Journals Connector (OSTI)

...cornstarch, 15 per cent cottonseed oil, and 5 per cent Hawk-Oser...extract2 and 1 drop of Percomorph Oil on alternate days. For the...nucleic acids was accomplished by heating in 0.1 N NaOH at 80 C. for...15:240-^5, 1955. 15. PRICE, J. M., and LAIRD,A...

Willis R. Foster and Fred G. Brazda

1958-04-01T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

141

BARRY OWEN JONES CITATION FOR AN HONORARY DEGREE

was a member of the House of Representatives representing the seat of Lalor. During the Hawke ministries he was a director of the State Opera of Victoria and for thirteen years Secretary of the Victorian Anti and the University of Technology, Sydney, and in Science from Macquarie University. His polymathic contributions have

Botea, Adi

142

Acoustic modulation effect of rotating stator/rotor interaction noise

order, B(k) is the number of rotor blades, (k) is the angular velocity of the rotor, (l) is the angular on the rotor blades and on the fixed parts. According to the Ffowcs-Williams and Hawk- ings analogy comes from the periodic forces on the rotor blades and the forces on the other static parts of the fan

Boyer, Edmond

143

Portable Graphical Tools for Concurrent Plasma Simulation October 18, 1996

Conference Plasma Reactor A Standardized Reactor Design for Research Purposes Experimental Model (left Faculty Sponsor: Dr. Stephen Taylor Abstract Low pressure reactors (less than 1.5 Torr) are used for largeÂscale simulations of these reactors. In order for Hawk to be convenient for the process engineers

144

Phase-field modeling of corrosion kinetics under dual-oxidants This article has been downloaded-field modeling of corrosion kinetics under dual-oxidants You-Hai Wen1 , Long-Qing Chen2 and Jeffrey A Hawk1 1 is proposed to simulate corrosion kinetics under a dual- oxidant atmosphere. It will be demonstrated

Chen, Long-Qing

145

1 List of species common names in English and French and the standard, 4-letter codes of birds database. English Name Code French Name English Name Code French Name Common Loon COLO Plongeon huard gorge rubis Broad-winged Hawk BWHA Petite Buse Belted Kingfisher BEKI Martin-pÃªcheur d'AmÃ©rique Red

146

White holes and eternal black holes

We investigate isolated white holes surrounded by vacuum, which correspond to the time reversal of eternal black holes that do not evaporate. We show that isolated white holes produce quasi- thermal Hawking radiation. The time reversal of this radiation, incident on a black hole precursor, constitutes a special preparation that will cause the black hole to become eternal.

Stephen D. H. Hsu

2011-11-16T23:59:59.000Z

147

Use of super-radiance in BH physics, so dE/dt alternatives with the possibility of needing a multiverse containment of BH structure, or embracing what Hawkings wrote up recently, namely a re do of the Event Horizon hypothesis as we know it.

Andrew Beckwith

2014-04-15T23:59:59.000Z

148

Thermodynamics of dual conformal field theories for Kerr-AdS black holes

Recently Gibbons et al. in [G. W. Gibbons et al. Class. Quant. Grav. 22, 1503 (2005)] defined a set of conserved quantities for Kerr-AdS black holes with the maximal number of rotation parameters in arbitrary dimension. This set of conserved quantities is defined with respect to a frame which is nonrotating at infinity. On the other hand, there is another set of conserved quantities for Kerr-AdS black holes, defined by Hawking et al. in [Hawking et al. Phys. Rev. D 59, 064005 (1999)], which is measured relative to a frame rotating at infinity. Gibbons et al. explicitly showed that the quantities defined by them satisfy the first law of black hole thermodynamics, while those quantities defined by Hawking et al. do not obey the first law. In this paper we discuss thermodynamics of dual CFTs to the Kerr-AdS black holes by mapping the bulk thermodynamic quantities to the boundary of the AdS space. We find that thermodynamic quantities of dual CFTs satisfy the first law of thermodynamics and Cardy-Verlinde formula only when these thermodynamic quantities result from the set of bulk quantities given by Hawking et al.. We discuss the implication of our results.

Cai Ronggen; Cao Liming; Pang Dawei [Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing 100080 (China); Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing 100080 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100039 (China)

2005-08-15T23:59:59.000Z

149

Probing Alpha-Vacua of Black Holes in LHC

Motivated by the idea of alpha-vacua in Schwarzschild spacetime, we studied the deformed spectrum of Hawking radiation. Such a deformation would leave signatures on the small black hole evaporation in LHC because their vacuum deviates from the Unruh state.

Tower Wang

2007-04-18T23:59:59.000Z

150

and third stages. Remembering the lightning that had caused problems for Apollo 12's takeoff, National in the CSM (dubbed Kitty Hawk) to effect lunar landing in the Fra Mauro region. Because of problems with a faulty switch in the abort guidance system, the Antares was forced into a manual landing at 0837 GMT

Merguerian, Charles

151

NEWTON, Ask a Scientist at Argonne National Labs

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Owl Predators Owl Predators Name: Mia Status: student Grade: K-3 Location: MN Country: USA Date: Winter 2011-2012 Question: What are the predators of a owl? Replies: Mia: Our largest adult owls have few predators. Smaller owls may be prey of other owls, long-eared owls are sometimes eaten by great horned owls, for example. Ground nesting owls, like short-eared owls, and especially nestlings, may be hunted by many predators, coyotes and other hawks and owls most likely. Nestlings of all birds, including owls may be hunted by other birds, raccoons, snakes and other animals that can climb trees. J. Elliott Hi Mia Predators of owls include: Opossums Racoons Hawks, Eagles and other raptors Other owls House cats Snakes that raid nests Accidents such as falling out of a nest, colliding with a tree, and electric power lines also contribute to owl mortality.

152

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hawking Ponders Infinity Hawking Ponders Infinity Ã’CAN YOU HEAR ME?Ã“ A substantial baritone, round and full; the accent borderline Scottish or Welsh, but schooled well short of a full brogue. A hint of wry in the tone, promising a barb or two before the nightÃ•s work was done. The voice immediately owned every expanse of the Arie Crown Theater at McCormick Place, ChicagoÃ•s gargantuan convention center by the lake. But who owned the voice? A motorized wheelchair rested at center stage, life support apparatus stacked behind the wheels, its inhabitant almost too still for reality. His head leaned unmoving against his right shoulder, his skeletal body angled in the chair like an oddly-bent wire coathanger. In front of him was a small custom computer console, where a minute twitch of his finger

153

Radio Monitoring Birds of Prey

Science Journals Connector (OSTI)

Abstract This paper is a consideration of field techniques rather than of equipment design. The first of three parts reviews applications of radio monitoring in bird of prey studies, with suggestions concerning terminology. There has been some radio telemetry of activity and incubation parameters, but most monitoring of raptors has involved radio tracking. This has included location of birds for investigation of movements, ranges, habitat utilization and roost sites, but could also be used for surveillance of what birds were doing. The second section describes techniques used in radio surveillance of a particularly secretive raptor, the goshawk, and presents original data on prey selection which were collected during studies of predation on woodpigeons and pheasants. Finally, there is an outline of how selection data were combined with predation rate measurements and hawk density estimates, obtained using radio tags as a Lincoln Index marker during hawk sightings, to determine the impact of predation on these economically important prey.

R.E. KENWARD

1980-01-01T23:59:59.000Z

154

Quantum Emission from Two-Dimensional Black Holes

We investigate Hawking radiation from two-dimensional dilatonic black holes using standard quantization techniques. In the background of a collapsing black hole solution the Bogoliubov coefficients can be exactly determined. In the regime after the black hole has settled down to an `equilibrium' state but before the backreaction becomes important these give the known result of a thermal distribution of Hawking radiation at temperature lambda/(2pi). The density matrix is computed in this regime and shown to be purely thermal. Similar techniques can be used to derive the stress tensor. The resulting expression agrees with the derivation based on the conformal anomaly and can be used to incorporate the backreaction. Corrections to the thermal density matrix are also examined, and it is argued that to leading order in perturbation theory the effect of the backreaction is to modify the Bogoliubov transformation, but not in a way that restores information lost to the black holes.

Steven B. Giddings; W. M. Nelson

2009-11-27T23:59:59.000Z

155

Black hole quantum tunnelling and black hole entropy correction

Parikh-Wilczek tunnelling framework, which treats Hawking radiation as a tunnelling process, is investigated again. As the first order correction, the log-corrected entropy-area relation naturally emerges in the tunnelling picture if we consider the emission of a spherical shell. The second order correction of the emission rate for the Schwarzschild black hole is calculated too. In this level, the result is still in agreement with the unitary theory, however, the entropy of the black hole will contain three parts: the usual Bekenstein-Hawking entropy, the logarithmic term and the inverse area term. In our results the coefficient of the logarithmic term is -1. Apart from a coefficient, Our correction to the black hole entropy is consistent with that of loop quantum gravity.

Jingyi Zhang

2008-06-15T23:59:59.000Z

156

Black Holes, Entropies, and Semiclassical Spacetime in Quantum Gravity

We present a coherent picture of the quantum mechanics of black holes. The picture does not require the introduction of any drastically new physical effect beyond what is already known; it arises mostly from synthesizing and (re)interpreting existing results in appropriate manners. We identify the Bekenstein-Hawking entropy as the entropy associated with coarse-graining performed to obtain semiclassical field theory from a fundamental microscopic theory of quantum gravity. This clarifies the issues around the unitary evolution, the existence of the interior spacetime, and the thermodynamic nature in black hole physics--any result in semiclassical field theory is a statement about the maximally mixed ensemble of microscopic quantum states consistent with the specified background, within the precision allowed by quantum mechanics. We present a detailed analysis of information transfer in Hawking emission and black hole mining processes, clarifying what aspects of the underlying dynamics are (not) visible in sem...

Nomura, Yasunori

2014-01-01T23:59:59.000Z

157

Supplement 20, Part 7, Parasite-Subject Catalogue: Hosts

.] Accipiter nisus "sparrow- hawk" (intestinal tract) Porrocaecum depressum Accipiter nisus Neocolpocephalum (N.) germanum nov. spec. Keymer, I. F., 1972 a Sorjonen, J.. 1971 a all from Finland Niak, A.; and Anwar, ?., 1972 a Iran Keymer, I. F., 1972..." (intestine) Centrorhynchus amphibius Centrorhynchus spp. Sorjonen, J., 1971 a Finland Schmidt, G. D.; and Kuntz, R. ?. , 1969 ? Taiwan Schmidt, G. D.; and Kuntz, R. E., 1971 a Wu-lai, Tai-pei Hsien, Taiwan Wu-lai, Nan-tao Hsien, Taiwan Schmidt...

Shaw, Judith H.; Edwards, Shirley J.; Rayburn, Jane D.; Tolson, Deborah A.; Hood, Martha W.

1976-01-01T23:59:59.000Z

158

An evaluation of avian use of a rice-wetland system

). I calculated a diversity index and richness for each site every time that site was sampled. I also calculated number of birds feeding per visit. I used statistical analysis sofhvare (SAS Inc. 1995) to perform my statistical analyses. Kruskal-Wallis... foragers, and surface glesners; Ground Foragers and Gleaners (GRND); Scavengers/Hawkers (HAWK); snd Other gleaners (OTHER), which included air salliers, bark gleaners, lower canopy gleaners, and marsh gleaners (Appendix C). I used Kruskal-Wallis...

Terry, Katherine Lynn

2012-06-07T23:59:59.000Z

159

Thermodynamical Properties of Horizons

We show, by using Regge calculus, that the entropy of any finite part of a Rindler horizon is, in the semi-classical limit, one quarter of the area of that part. We argue that this result implies that the entropy associated with any horizon of spacetime is, in semi-classical limit, one quarter of its area. As an example, we derive the Bekenstein-Hawking entropy law for the Schwarzschild black hole.

J. Makela; A. Peltola

2002-05-30T23:59:59.000Z

160

Handbook of Amyotrophic Lateral Sclerosis

Science Journals Connector (OSTI)

..., and he has been appropriately honored for his physical achievements. Hawking's conclusion gives his key to survival: he emphasizes living with amyotrophic lateral sclerosis rather than dying of the disease -- quite different approaches. The handbook contains 31 chapters contributed by 52 authors. The... These are exciting times for investigators of neuromuscular diseases. With the explosion of information about the human genome, we are advancing on the mysteries of many diseases, such as Duchenne's muscular dystrophy, that were formerly thought to be ...

Lange D.J.

1993-06-10T23:59:59.000Z

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they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

161

Imaging single cells in a beam of live cyanobacteria with an X-ray laser

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

This entry contains ten diffraction patterns, and reconstructions images, of individual living Cyanobium gracile cells, imaged using 517 eV X-rays from the LCLS XFEL. The Hawk software package was used for phasing. The Uppsala aerosol injector was used for sample injection, assuring very low noise levels. The cells come from various stages of the cell cycle, and were imaged in random orientations.

Schot, Gijs, vander

162

First law of thermodynamics in IR modified Ho?ava-Lifshitz gravity

Science Journals Connector (OSTI)

We study the first law of thermodynamics in IR modified Ho?ava-Lifshitz spacetime. Based on the Bekenstein-Hawking entropy, we obtain the integral formula and the differential formula of the first law of thermodynamics for the Kehagias-Sfetsos black hole by treating ? as a new state parameter and redefining a mass that is just equal to MADM obtained by Myung [32] if we take ?=3?/8.

Mengjie Wang; Jiliang Jing; Chikun Ding; Songbai Chen

2010-04-15T23:59:59.000Z

163

First law of thermodynamics in IR modified Horava-Lifshitz gravity

We study the first law of thermodynamics in IR modified Horava-Lifshitz spacetime. Based on the Bekenstein-Hawking entropy, we obtain the integral formula and the differential formula of the first law of thermodynamics for the Kehagias-Sfetsos black hole by treating {omega} as a new state parameter and redefining a mass that is just equal to M{sub ADM} obtained by Myung [32] if we take {alpha}=3{pi}/8.

Wang Mengjie; Jing Jiliang; Ding Chikun; Chen Songbai [Institute of Physics and Department of Physics, Hunan Normal University, Changsha, Hunan 410081 (China) and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan Normal University, Changsha, Hunan 410081 (China)

2010-04-15T23:59:59.000Z

164

On the Quantum-Corrected Black Hole Thermodynamics

Bekenstein-Hawking Black hole thermodynamics should be corrected to incorporate quantum gravitational effects. Generalized Uncertainty Principle(GUP) provides a perturbational framework to perform such modifications. In this paper we consider the most general form of GUP to find black holes thermodynamics in microcanonical ensemble. Our calculation shows that there is no logarithmic pre-factor in perturbational expansion of entropy. This feature will solve part of controversies in literatures regarding existence or vanishing of this pre-factor.

Kourosh Nozari; S. Hamid Mehdipour

2005-04-21T23:59:59.000Z

165

Black Hole Thermodynamics and Electromagnetism

We show a strong parallel between the Hawking, Beckenstein black hole Thermodynamics and electromagnetism: When the gravitational coupling constant transform into the electromagnetic coupling constant, the Schwarzchild radius, the Beckenstein temperature, the Beckenstein decay time and the Planck mass transform to respectively the Compton wavelength, the Hagedorn temperature, the Compton time and a typical elementary particle mass. The reasons underlying this parallalism are then discussed in detail.

Burra G. Sidharth

2005-07-15T23:59:59.000Z

166

Of the Black Hole Thermodynamics

About thirty years ago, Bekenstein and Hawking introduced three basic concepts relating to black hole, namely, the "area entropy", "gravitation temperature" and "thermal radiation". The author analyzes these concepts systematically and concludes that they are mostly inadequate or wrong. He points out that a black hole's taking in thermal radiation from the space is an energy-gathering process. It is special, even extraordinary. It reduces entropy, violating Clausius' second law.

Xinyong Fu

2005-01-11T23:59:59.000Z

167

Extremal dilatonic black holes in 4D Gauss-Bonnet gravity

This is a report of our recent investigation on the extremal dilatonic black holes in four dimensional Gauss-Bonnet gravity. We found that a global solution can exist only when the dilaton coupling is less than a critical value which can be determined numerically. Moreover, the black hole horizon is stretched by the Gauss-Bonnet correction and the entropy is twice the value given by Bekenstein-Hawking formula.

Chiang-Mei Chen

2007-12-29T23:59:59.000Z

168

On the Architecture of Spacetime Geometry

We propose entanglement entropy as a probe of the architecture of spacetime in quantum gravity. We argue that the leading contribution to this entropy satisfies an area law for any sufficiently large region in a smooth spacetime, which, in fact, is given by the Bekenstein-Hawking formula. This conjecture is supported by various lines of evidence from perturbative quantum gravity, simplified models of induced gravity and loop quantum gravity, as well as the AdS/CFT correspondence.

Eugenio Bianchi; Robert C. Myers

2012-12-20T23:59:59.000Z

169

On the Stability of Black Holes at the LHC

The eventual production of mini black holes by proton-proton collisions at the LHC is predicted by theories with large extra dimensions resolvable at the Tev scale of energies. It is expected that these black holes evaporate shortly after its production as a consequence of the Hawking radiation. We show that for theories based on the ADS/CFT correspondence, the produced black holes may have an unstable horizon, which grows proportionally to the square of the distance to the collision point.

M. D. Maia; E. M. Monte

2008-08-19T23:59:59.000Z

170

The origin of self-similar (according to Y.Kulakov) structure of the Universe is discussed from a position of the theory of dynamic systems (DS). A probable nature of the isomorphism of DS configurations of different levels is revealed. Nucleon DS configuration like black hole (BH) might be acquired by the last as a result of Hawking radiation of initial BH and serve further as a genome of the Universe development.

I. A. Kuchin; S. S. Boichenko; Y. I. Kuchin

2005-07-29T23:59:59.000Z

171

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

9 Archives 9 Archives Archives: Pre-2006 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 Mo-Sci Corporation to Manufacture, Market SRNL's Unique Glass Microspheres AIKEN, S.C. (December 17, 2009) - A licensing agreement between the U.S. Department of Energy's Savannah River National Laboratory (SRNL) and specialty glass provider Mo-Sci Corporation will make SRNL's unique Porous Walled Hollow Glass Microspheres available for use in targeted drug delivery, hydrogen storage and other uses, including applications still being developed. MORE Â» SRNL Establishes Presence at Charleston's SeaHawk AIKEN, S.C. (Nov. 17, 2009) - To support homeland security initiatives, the U.S. Department of Energy's Savannah River National Laboratory has established a permanent presence at the SeaHawk interagency operations center (IOC). SeaHawk was established by Congress in 2003 and located at the Port of Charleston (S.C.) as a collaborative initiative designed to bring multiple agencies together to enhance port security operations and coordination among federal, state and local agencies. MORE Â»

172

Revisit emission spectrum and entropy quantum of the Reissner-Nordström black hole

Banerjee and Majhi's recent work shows that black hole's emission spectrum could be fully reproduced in the tunneling picture, where, as an intriguing technique, the Kruskal extension was introduced to connect the left and right modes inside and outside the horizon. Some attempt, as an extension, was focused on producing the Hawking emission spectrum of the (charged) Reissner-Nordstr\\"{o}m black hole in the Banerjee-Majhi's treatment. Unfortunately, the Kruskal extension in their observation was so badly defined that the ingoing mode was classically forbidden traveling towards the center of black hole, but could quantum tunnel across the horizon with the probability $\\Gamma=e^{-\\pi \\omega_0/\\kappa_+}$. This tunneling picture is unphysical. With this point as a central motivation, in this paper we first introduce such a suitable Kruskal extension for the (charged) Reissner-Nordstr\\"{o}m black hole that a perfect tunneling picture can be provided during the charged particle's emission. Then, under the new Kruskal extension, we revisit the Hawking emission spectrum and entropy spectroscopy as tunneling from the charged black hole. The result shows that the tunneling method is so universally robust that the Hawking blackbody emission spectrum from a charged black hole can be well reproduced in the tunneling mechanism, and its induced entropy quantum is a much better approximation for the forthcoming quantum gravity theory.

Qing-Quan Jiang

2012-10-15T23:59:59.000Z

173

Black hole radiation in the presence of a short distance cutoff

Science Journals Connector (OSTI)

A derivation of the Hawking effect is given which avoids reference to field modes above some cutoff frequency ?c?M-1 in the free-fall frame of the black hole. To avoid reference to arbitrarily high frequencies, it is necessary to impose a boundary condition on the quantum field in a timelike region near the horizon, rather than on a (spacelike) Cauchy surface either outside the horizon or at early times before the horizon forms. Because of the nature of the horizon as an infinite redshift surface, the correct boundary condition at late times outside the horizon cannot be deduced, within the confines of a theory that applies only below the cutoff, from initial conditions prior to the formation of the hole. A boundary condition is formulated which leads to the Hawking effect in a cutoff theory. It is argued that it is possible the boundary condition is not satisfied, so that the spectrum of black hole radiation may be significantly different from that predicted by Hawking, even without the back reaction near the horizon becoming of order unity relative to the curvature.

Ted Jacobson

1993-07-15T23:59:59.000Z

174

We study the Hawking process on lattices falling into static black holes. The motivation is to understand how the outgoing modes and Hawking radiation can arise in a setting with a strict short distance cutoff in the free-fall frame. We employ two-dimensional free scalar field theory. For a falling lattice with a discrete time-translation symmetry we use analytical methods to establish that, for Killing frequency $\\omega$ and surface gravity $\\kappa$ satisfying $\\kappa\\ll\\omega^{1/3}\\ll 1$ in lattice units, the continuum Hawking spectrum is recovered. The low frequency outgoing modes arise from exotic ingoing modes with large proper wavevectors that "refract" off the horizon. In this model with time translation symmetry the proper lattice spacing goes to zero at spatial infinity. We also consider instead falling lattices whose proper lattice spacing is constant at infinity and therefore grows with time at any finite radius. This violation of time translation symmetry is visible only at wavelengths comparable to the lattice spacing, and it is responsible for transmuting ingoing high Killing frequency modes into low frequency outgoing modes.

Steven Corley; Ted Jacobson

1998-03-26T23:59:59.000Z

175

Quantum vacuum radiation in optical glass

A recent experimental claim of the detection of analogue Hawking radiation in an optical system [PRL 105 (2010) 203901] has led to some controversy [PRL 107 (2011) 149401, 149402]. While this experiment strongly suggests some form of particle creation from the quantum vacuum (and hence it is per se very interesting), it is also true that it seems difficult to completely explain all features of the observations by adopting the perspective of a Hawking-like mechanism for the radiation. For instance, the observed photons are emitted parallel to the optical horizon, and the relevant optical horizon is itself defined in an unusual manner by combining group and phase velocities. This raises the question: Is this really Hawking radiation, or some other form of quantum vacuum radiation? Naive estimates of the amount of quantum vacuum radiation generated due to the rapidly changing refractive index --- sometimes called the dynamical Casimir effect --- are not encouraging. However we feel that naive estimates could be misleading depending on the quantitative magnitude of two specific physical effects: "pulse steepening" and "pulse cresting". Plausible bounds on the maximum size of these two effects results in estimates much closer to the experimental observations, and we argue that the dynamical Casimir effect is now worth additional investigation.

Stefano Liberati; Angus Prain; Matt Visser

2011-11-01T23:59:59.000Z

176

1994 Northern Goshawk inventory on portions of Los Alamos National Laboratory, Los Alamos, NM

Northern goshawks (Accipiter gentilis) (hereafter referred to as goshawk) are large forest dwelling hawks. They are the largest species of the Accipiter genus which also includes sharp-shinned hawks (A. striatus) and the Cooper`s hawk (A. cooperii). Goshawks are holarctic in distribution and nest in coniferous, deciduous, and mixed species forests. In the southwest they primarily nest in ponderosa pine (Pinus ponderosa), mixed species, and spruce-fir forests. Goshawks may be declining in population and reproduction in the southwestern United States. In 1982 the USDA-Forest Service listed the goshawk as a {open_quotes}sensitive species{close_quotes} and in 1992 the U.S. Fish and Wildlife Service listed the goshawk as a {open_quotes}Category 2 species{close_quotes} in accordance with the Endangered Species Act. Reasons for the possible decline in goshawk populations include timber harvesting resulting in the loss of nesting habitat, toxic chemicals, and the effects of drought, fire, and disease. Thus, there is a need to determine their population status and assess impacts of management activities in potential goshawk habitat. Goshawk inventory was conducted during the 1993 nesting season with no adult goshawk responses detected within the LANL survey area. As noted by Sinton and Kennedy, these results may be interpreted in several ways: (1) no goshawk territory(ies) occur in the inventoried area; (2) goshawk territory(ies) exist but have failed prior to the survey and thus were not detected; or (3) territory(ies) exist and were successful but the goshawks did not respond to tapes or their responses were undetected by the observer. For those reasons, a goshawk inventory was conducted in 1994. This report summarizes the results of this inventory.

Sinton, D.T.; Kennedy, P.L. [Colorado State Univ., Fort Collins, CO (United States)

1995-01-01T23:59:59.000Z

177

Microscopic quantum structure of black hole and vacuum versus quantum statistical origin of gravity

The Planckon densely piled model of vacuum is proposed. Based on this model, the microscopic quantum structure of Schwarzschild black hole and quantum statistical origin of its gravity are studied. The cutoff of black hole horizon leads to Casimir effect inside the horizon. This effect makes the inside vacuum has less zero quantum fluctuation energy than that of outside vacuum and the spin 1/2 radiation hole excitations are resulted inside the horizon. The mean energy of the radiation hole excitations is related to the temperature decrease of the Hawking-Unruh type by the period law of the Fermion temperature greens function and a temperature difference as well as gravity are created on the horizon. A dual relation of the gravity potentials between inside and outside regions of the black hole is found. An attractor behaviour of the horizon surface is unveiled. The gravity potential inside the black hole is linear in radial coordinate and no singularity exists at the origin of the black hole, in contrast to the conventional conjecture. All the particles absorbed by the black hole have fallen down to the horizon and converted into spin 1/2 radiation quanta with the mean energy related to the Hawking-Unruh temperature, the thermodynamic equilibrium and the mechanical balance make the radiation quanta be tightly bound in the horizon. The gravitation mass $2M$ and physical mass $M$ of the black hole are calculated. The calculated entropy of the black hole is well consistent with Hawking. Outside the horizon, there exist thermodynamic non-equilibrium and mechanical non-balance which lead to an outward centrifugal energy flow and an inward gravitation energy flow. The lost vacuum energy in the negative gravitation potential region has been removed to the black hole surface to form a spherical Planckon shell with the thickness of Planckon diameter so that energy conservation is guaranteed.

Shun-Jin Wang

2014-10-28T23:59:59.000Z

178

Two Line Subject Title One Line Title

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

& Development & Development Advanced Alloy Fabrication Jeffrey A. Hawk & Paul D. Jablonski Materials Research Engineer & Metallurgist, NETL Wednesday, November 25, 2012 â€¹#â€º Technology or Capability Overview * Computer Modeling for Alloy Design & Life Prediction * Melting, Casting, Fabrication & Heat Treatment * Environmental Characterization * Mechanical Testing & Evaluation * Microstructure Characterization & Analysis â€¹#â€º Technology or Capability Overview * Computer Modeling for Alloy Design & Life Prediction * Melting, Casting, Fabrication & Heat Treatment * Environmental Characterization * Mechanical Testing & Evaluation * Microstructure Characterization & Analysis â€¹#â€º Melting and Fabrication Facilities

179

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Uranium Processing Facility Uranium Processing Facility Harry E. Peters Y-12 Site Office Federal Project Director Uranium Processing Facility Project February 8, 2012 APPROVED FOR PUBLIC RELEASE This document has been approved for release to the public by: /s/ Scott A. Hawks 2/9/12 YSO Classification Officer Date The Nation's EU Processing Facility Mission: Ensuring the Nation's enriched uranium processing is secure, safe, and efficient. UPF-Key to Y-12 Transformation Today Future * 9212 is past end-of-life * Existing EU facilities don't meet modern nuclear safety or security standards

180

3D Flat Holography: Entropy and Logarithmic Corrections

We compute the leading corrections to the Bekenstein-Hawking entropy of the Flat Space Cosmological (FSC) solutions in 3D flat spacetimes, which are the flat analogues of the BTZ black holes in AdS3. The analysis is done by a computation of density of states in the dual 2D Galilean Conformal Field Theory and the answer obtained by this matches with the limiting value of the expected result for the BTZ inner horizon entropy as well as what is expected for a generic thermodynamic system. Along the way, we also develop other aspects of holography of 3D flat spacetimes.

Arjun Bagchi; Rudranil Basu

2013-12-19T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

181

Gravitational tests of the Generalized Uncertainty Principle

We compute the corrections to the Schwarzschild metric necessary to reproduce the Hawking temperature derived from a Generalized Uncertainty Principle (GUP), so that the GUP deformation parameter is directly linked to the deformation of the metric. Using this modified Schwarzschild metric, we compute corrections to the standard General Relativistic predictions for the light deflection and perihelion precession, both for planets in the solar system and for binary pulsars. This analysis allows us to set bounds for the GUP deformation parameter from well-known astronomical measurements.

Scardigli, Fabio

2014-01-01T23:59:59.000Z

182

Geodesic Nucleation and Evolution of a de Sitter Brane

Within the framework of Geodesic Brane Gravity, the deviation from General Relativity is parameterized by the conserved bulk energy. The corresponding geodesic evolution/nucleation of a de-Sitter brane is shown to be exclusively driven by a double-well Higgs potential, rather than by a plain cosmological constant. The (hairy) horizon serves then as the locus of unbroken $Z_{2}$ symmetry. The quartic structure of the scalar potential, singled out on finiteness grounds of the total (including the dark component) energy density, chooses the Hartle-Hawking no-boundary proposal.

Aharon Davidson; David Karasik; Yoav Lederer

2005-09-30T23:59:59.000Z

183

Stability of Flat Space to Singular Instantons

Hawking and the author have proposed a class of singular, finite action instantons for defining the initial conditions for inflation. Vilenkin has argued they are unacceptable. He exhibited an analogous class of asymptotically flat instantons which on the face of it lead to an instability of Minkowski space. However, all these instantons must be defined by introducing a constraint into the path integral, which is then integrated over. I show that with a careful definition these instantons do not possess a negative mode. Infinite flat space is therefore stable against decay via singular instantons.

Neil Turok

1999-01-27T23:59:59.000Z

184

Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. The Fermi Gamma-ray Space Telescope observatory offers increased sensitivity to the gamma-ray bursts produced by PBHs with an initial mass of $\\sim 5\\times 10^{14}$ g expiring today. PBHs are candidate progenitors of unidentified Gamma-Ray Bursts (GRBs) that lack X-ray afterglow. We propose spectral lag, which is the temporal delay between the high and low energy pulses, as an efficient method to identify PBH evaporation events with the Fermi Large Area Telescope (LAT).

T. N. Ukwatta; Jane H. MacGibbon; W. C. Parke; K. S. Dhuga; S. Rhodes; A. Eskandarian; N. Gehrels; L. Maximon; D. C. Morris

2010-03-23T23:59:59.000Z

185

Spectral Lags of Gamma-Ray Bursts from Primordial Black Hole (PBH) Evaporations

Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. PBHs with an initial mass of 5.0 * 10^14 g should be expiring today with a burst of high energy particles. Evaporating PBHs in the solar neighborhood are candidate Gamma-Ray Bursts (GRBs) progenitors. We propose spectral lag, which is the temporal delay between the high energy photon pulse and the low energy photon pulse, as a possible method to detect PBH evaporation events with the Fermi Gamma-ray Space Telescope Observatory.

T. N. Ukwatta; J. H. MacGibbon; W. C. Parke; K. S. Dhuga; A. Eskandarian; N. Gehrels; L. Maximon; D. C. Morris

2009-08-14T23:59:59.000Z

186

Kappa - Poincare dispersion relations and the black hole radiation

Following the methods developed by Corley and Jacobson, we consider qualitatively the issue of Hawking radiation in the case when the dispersion relation is dictated by quantum kappa-Poincare algebra. This relation corresponds to field equations that are non-local in time, and, depending on the sign of the parameter kappa, to sub- or superluminal signal propagation. We also derive the conserved inner product, that can be used to count modes, and therefore to obtain the spectrum of black hole radiation in this case.

A. Blaut; J. Kowalski-Glikman; D. Nowak-Szczepaniak

2001-08-28T23:59:59.000Z

187

Information loss and anomalous scattering

Science Journals Connector (OSTI)

The approach of 't Hooft to the puzzles of black hole evaporation can be applied to a simpler system with analogous features. The system is (1+1)-dimensional electrodynamics in a linear dilation background. Analogues of black holes, Hawking radiation, and evaporation exist in this system. In perturbation theory there appears to be an information paradox but this gets resolved in the full quantum theory and there exists an exact S matrix, which is fully unitary and information conserving. 't Hooft's method gives the leading terms in a systematic approximation to the exact result.

Amanda Peet; Leonard Susskind; Lárus Thorlacius

1992-10-15T23:59:59.000Z

188

ARCO moves to spark U. S. activity, spread risk

This paper reports that one US major oil company has taken the offensive to combat tightness of drilling capital in the US and the overseas flight of interest in elephant hunting. ARCO Oil and Gas Co., with substantial acreage and seismic data covering most of the US Lower 48 states, s communicating with a broad audience to try to make activity happen on its properties. ARCO is looking to bring others in on its prospects, hawk seismic data, and take deals from others. On some acreage that internal funds are not available to evaluate, ARCO was offering 100% farmounts.

Petzet, G.A.

1992-07-13T23:59:59.000Z

189

Primordial Black Holes as Heat Sources for Living Systems with Longest Possible Lifetimes

Just forty years ago, Hawking wrote his famous paper on primordial black holes (PBH). There have been since innumerable discussions on the consequences of the existence of such exotic objects and ramifications of their properties. Here we suggest that PBH's in an ever expanding universe (as implied by dark energy domination, especially of a cosmological constant) could be the ultimate repository for long lived living systems. PBH's having solar surface temperatures would last 10^32 years as a steady power source and should be considered in any discussion on exobiological life.

C Sivaram; Kenath Arun; Kiren O V

2014-02-14T23:59:59.000Z

190

Undulations from amplified low frequency surface waves

We study the linear scattering of gravity waves in longitudinal inhomogeneous stationary flows. When the flow becomes supercritical, it is known that counterflow propagating shallow waves are blocked and converted into deep waves. Here we show that in the zero-frequency limit, the reflected waves are amplified in such a way that the free surface develops an undulation, i.e., a zero-frequency wave of large amplitude with nodes located at specific places. This amplification involves negative energy waves and implies that flat surfaces are unstable against incoming perturbations of arbitrary small amplitude. The relation between this instability and black hole radiation (the Hawking effect) is established.

Coutant, Antonin, E-mail: antonin.coutant@aei.mpg.de [Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muhlenberg 1, 14476 Golm (Germany)] [Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muhlenberg 1, 14476 Golm (Germany); Parentani, Renaud, E-mail: renaud.parentani@th.u-psud.fr [Laboratoire de Physique Théorique, CNRS UMR 8627, Bâtiment 210, Université Paris-Sud 11, 91405 Orsay Cedex (France)] [Laboratoire de Physique Théorique, CNRS UMR 8627, Bâtiment 210, Université Paris-Sud 11, 91405 Orsay Cedex (France)

2014-04-15T23:59:59.000Z

191

Feather mites (Acarina: Analgesoidea) of some Texan and Mexican falconiform and strigiform birds

species found on eacl!. Harris haw!i-Parabuteo unicinc. tu harris! (Audubon) P eudal)biotin&rs rniilvu'in is (Trouessart) Caracara-Caracars c?&eriway audubonii (Cassir&) Ga?&ucinia hyalothrix Gaud and iouchet Red-tailed Hawk-B& tco jama...&censis borealis (Gmelin) Gabucinia tistata sp. n. Swainson's I. awk ? Bi tco swa&'neon! Btnnp:. rte ztveous tex i. . us sp. n. Long horned o I- u!&o virgin!anus G . el! n Protaiecs "ttenuatus (Buchholz) Barred o. rl-Sirix var!a Bangs Dernonoton serve!. us...

Elbihari, Sabir

2012-06-07T23:59:59.000Z

192

Gravitational tests of the Generalized Uncertainty Principle

We compute the corrections to the Schwarzschild metric necessary to reproduce the Hawking temperature derived from a Generalized Uncertainty Principle (GUP), so that the GUP deformation parameter is directly linked to the deformation of the metric. Using this modified Schwarzschild metric, we compute corrections to the standard General Relativistic predictions for the light deflection and perihelion precession, both for planets in the solar system and for binary pulsars. This analysis allows us to set bounds for the GUP deformation parameter from well-known astronomical measurements.

Fabio Scardigli; Roberto Casadio

2014-07-01T23:59:59.000Z

193

small ships, the brig Boston and schooner Hawk, but was roughly handled in an engagement with an inferior British warship, the twenty-gun Glasgow, as it cruised off Block Island on April 6. Although outgunned and outnumbered, Captain Tyringham Howe... Monk and 32-gun frigate Quebec, Barney directed his helmsman to obey the opposite of his orders yelled within earshot of General Monk. The ruse worked; Barney and his crew soon captured General Monk with a loss of only four men dead and eleven...

Duerksen, Benjamin

2012-07-16T23:59:59.000Z

194

Phenomenological Description of the Interior of the Schwarzschild Black Hole

We discuss a sufficiently large 4-dimensional Schwarzschild black hole which is in equilibrium with a heat bath. In other words, we consider a black hole which has grown up from a small one in the heat bath adiabatically. We express the metric of the interior of the black hole in terms of two functions: One is the intensity of the Hawking radiation, and the other is the ratio between the radiation energy and the pressure in the radial direction. Especially in the case of conformal matters we check that it is a self-consistent solution of the semi-classical Einstein equation, $G_{\\mu\

Hikaru Kawai; Yuki Yokokura

2014-09-19T23:59:59.000Z

195

Thermodynamics of dilaton-axion black holes

Considering a generalized action for the Einstein-Maxwell theory in four dimensions coupled to scalar and pseudoscalar fields, the thermodynamic properties of asymptotically flat black hole solutions in such a background are investigated. Bekenstein-Hawking area-entropy law is verified for these class of black holes. From the property of specific heat, it is shown that such black holes can be stable for a certain choice of the parameters like charge, mass, and the scalar vacuum expectation value. The possibility of a black hole phase transition is discussed in this context.

Ghosh, Tanwi; SenGupta, Soumitra [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta-700 032 (India)

2008-12-15T23:59:59.000Z

196

Black hole evaporation within a momentum-dependent metric

We investigate the black hole thermodynamics in a 'deformed' relativity framework where the energy-momentum dispersion law is Lorentz-violating and the Schwarzchild-like metric is momentum-dependent with a Planckian cutoff. We obtain net deviations of the basic thermodynamical quantities from the Hawking-Bekenstein predictions: actually, the black hole evaporation is expected to quit at a nonzero critical mass value (of the order of the Planck mass), leaving a zero temperature remnant, and avoiding a spacetime singularity. Quite surprisingly, the present semiclassical corrections to black hole temperature, entropy, and heat capacity turn out to be identical to the ones obtained within some quantum approaches.

Salesi, G.; Di Grezia, E. [Universita Statale di Bergamo, Facolta di Ingegneria, viale Marconi 5, I-24044 Dalmine (Italy) and Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, I-20133 Milan (Italy)

2009-05-15T23:59:59.000Z

197

Non-Extensive Black Hole Thermodynamics Estimate for Power-Law Particle Spectra

We point out that by considering the Hawking-Bekenstein entropy of Schwarzschild black hole horizons as a non-extensive Tsallis entropy, its additive formal logarithm, coinciding with the Renyi entropy, generates an equation of state with positive heat capacity above a threshold energy. Based on this, the edge of stability is conjectured to be trans-Planckian, i.e. being in the quantum range. From this conjecture an estimate arises for the q-parameter in the Renyi entropy, (q=2/pi^2), also manifested in the canonical power-law distribution of high energy particles (q ~ 1.2 for quark matter).

Tamas S. Biro

2010-11-15T23:59:59.000Z

198

The second law of thermodynamics, TCP, and Einstein causality in anti-de Sitter space-time

If the vacuum is passive for uniformly accelerated observers in anti-de Sitter space-time (i.e. cannot be used by them to operate a "perpetuum mobile"), they will (a) register a universal value of the Hawking-Unruh temperature, (b) discover a TCP symmetry, and (c) find that observables in complementary wedge-shaped regions are commensurable (local) in the vacuum state. These results are model independent and hold in any theory which is compatible with some weak notion of space-time localization.

Detlev Buchholz; Martin Florig; Stephen J. Summers

1999-05-25T23:59:59.000Z

199

Science Journals Connector (OSTI)

Hawking has recently pointed out that black holes cannot evaporate and disappear through wormholes because the entropy of a baby universe would not equal its size squared times some proportionality constant. In this report it is shown that multiply connected Euclidean wormhole spacetimes can be associated with nonlinear dynamic laws which are analogous to those of nonequilibrium thermodynamics, making plausible a full generalization of thermodynamics encompassing both nonequilibrium and gravitational effects. It is seen that both at equilibrium and out of it baby universe thermodynamics can provide the right relation between the size of the originating black hole and its entropy.

Pedro F. González-Díaz

1996-07-15T23:59:59.000Z

200

Gravity and quantum theory cause the Universe to be spontaneously created out of nothing. Most of these universes are quite unlike our own but we select out a subset that are compatible with what we observe. Please note that Professor Hawking's talk will be broadcasted in the following rooms : TH auditorium (4-3-006) TE auditorium (30-7-018) 40-S2-A01 40-S2-C01 BE Meyrin (6-2-024) BE Prévessin (864-1-D02)

None

2011-10-06T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

201

Primordial Black Holes as Heat Sources for Living Systems with Longest Possible Lifetimes

Just forty years ago, Hawking wrote his famous paper on primordial black holes (PBH). There have been since innumerable discussions on the consequences of the existence of such exotic objects and ramifications of their properties. Here we suggest that PBH's in an ever expanding universe (as implied by dark energy domination, especially of a cosmological constant) could be the ultimate repository for long lived living systems. PBH's having solar surface temperatures would last 10^32 years as a steady power source and should be considered in any discussion on exobiological life.

Sivaram, C; O, Kiren

2014-01-01T23:59:59.000Z

202

Broader source: Energy.gov (indexed) [DOE]

Legal Lessons You Need To Learn Legal Lessons You Need To Learn 1 1 "Legal Landmines for Small Contractors" United States Department of Energy 12th Annual Small Business Conference & Expo 11 May 2011 Kansas City, Missouri Mark R. "Hawk" Thomas, Esq. Reid Law PC Legal Lessons You Need To Learn 2 2 Federal Contracts - IP - Business Ventures ____________________________________________ SBA Certifications Teaming & Joint Ventures Subcontracts & Suppliers Solicitations & Bids Cost & Labor Standards Contract Negotiation ITAR & Export Control Inventions & Data Rights Inspection & Warranty Size Determinations Protests & Appeals Contract Termination Dispute Resolution False Claims & Fraud Suspension & Debarment ______________________________________________

203

We trace the origin of the black hole entropy S, replacing a black hole by a quasiblack hole. Let the boundary of a static body approach its own gravitational radius, in such a way that a quasihorizon forms. We show that if the body is thermal with the temperature taking the Hawking value at the quasihorizon limit, it follows, in the nonextremal case, from the first law of thermodynamics that the entropy approaches the Bekenstein-Hawking value S=A/4. In this setup, the key role is played by the surface stresses on the quasihorizon and one finds that the entropy comes from the quasihorizon surface. Any distribution of matter inside the surface leads to the same universal value for the entropy in the quasihorizon limit. This can be of some help in the understanding of black hole entropy. Other similarities between black holes and quasiblack holes such as the mass formulas for both objects had been found previously. We also discuss the entropy for extremal quasiblack holes, a more subtle issue.

Lemos, Jose P. S.; Zaslavskii, Oleg B. [Centro Multidisciplinar de Astrofisica-CENTRA, Departamento de Fisica, Instituto Superior Tecnico-IST, Universidade Tecnica de Lisboa-UTL, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Astronomical Institute of Kharkov, V. N. Karazin National University, 35 Sumskaya Street, Kharkov, 61022 (Ukraine)

2010-03-15T23:59:59.000Z

204

Properties of radiation near the black-hole horizon and the second law of thermodynamics

Science Journals Connector (OSTI)

By considering a gedanken experiment of adiabatically lowering a box containing matter with rest energy E and entropy S into a black hole, Bekenstein claimed that the necessary condition for the validity of the generalized second law of thermodynamics is S/E?2?R, where R is the effective radius of the box. Unruh and Wald claimed that this condition is not necessary but the acceleration radiation can guarantee the generalized second law. In this paper, we point out that the Unruh-Wald conclusion does not hold because Hawking radiation near the horizon is not thermal. Bekenstein’s conclusion does not hold because the thin box approximation is not correct near the horizon. Neither Hawking radiation (or acceleration radiation) nor S/E?2?R can guarantee the second law. We have sufficient reasons to conjecture that gravitation can influence the matter equation of state. For radiation, the usual equation of state ?=?T4 and S=4/3?T3 does not hold in the strong gravitation field, e.g., near the black-hole horizon. We derive the equation of state for radiation near the horizon and find that it is very different from the equation in flat spacetime. The second law of thermodynamics can be satisfied if we impose some restrictions on one parameter of the equation of state. As a corollary, we get an upper bound on S/E which resembles Bekenstein’s result.

Li-Xin Li and Liao Liu

1992-10-15T23:59:59.000Z

205

Geometry of the Infalling Causal Patch

The firewall paradox states that an observer falling into an old black hole must see a violation of unitarity, locality, or the equivalence principle. Motivated by this remarkable conflict, we analyze the causal structure of black hole spacetimes in order to determine whether all the necessary ingredients for the paradox fit within a single observer's causal patch. We particularly focus on the question of whether the interior partner modes of the outgoing Hawking quanta can, in principle, be measured by an infalling observer. Since the relevant modes are spread over the entire sphere, we answer a simple geometrical question: can any observer see an entire sphere behind the horizon? We find that for all static black holes in 3+1 and higher dimensions, with any value of the cosmological constant, no single observer can see both the early Hawking radiation and the interior modes. We present a detailed description of the causal patch geometry of the Schwarzschild black hole in 3+1 dimensions, where an infalling o...

Freivogel, Ben; Kabir, Laurens; Yang, I-Sheng

2014-01-01T23:59:59.000Z

206

Making STEM Personal | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Making STEM Personal Making STEM Personal Making STEM Personal March 29, 2013 - 3:51pm Addthis Occupations in science, technology, engineering, and mathematics (STEM) are among the fastest growing fields, offering well-paying opportunities to better explore, understand, and improve the world. To celebrate Women's History Month, DOE recently introduced an online Women @ Energy series that profiles DOE women involved in STEM., Included in the Women @ Energy series are OE's Assistant Secretary Patricia Hoffman and Carol Hawk who manages the Cybersecurity for Energy Delivery Systems Program. In her profile, Pat Hoffman talks about being inspired by her aunt who worked in the scientific field, a woman who excited Pat's imagination: "She told me about all of the different materials that were going to be

207

Energy Secretary Chu Announces Montana Schools Win National Student

Broader source: Energy.gov (indexed) [DOE]

Montana Schools Win National Student Montana Schools Win National Student Efficiency Competition Energy Secretary Chu Announces Montana Schools Win National Student Efficiency Competition May 2, 2012 - 3:05pm Addthis WASHINGTON, D.C. - Secretary of Energy Steven Chu today announced the winners of the America's Home Energy Education Challenge, a national student competition designed to encourage students and their families to take action to start saving money by saving energy. A team of students from five schools in rural Carter County, Montana - Alzeda Elementary School, Carter County High School, Ekalaka Elementary School (K-8th grade), Hammond School (K-8th grade) and Hawks Home School - was declared the national winner for successfully reducing their home energy use by 3.4 percent, working with local utility companies and the community,

208

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Zoology Archives Zoology Archives Zoology Archives, Since May 2000 Table of Contents: Bat Pets Insect Bites Earthworms and Soil Wren House Jumping Insects Killdeer Nesting Intolerance or Allergy to Milk Art and Mitosis Injured Animals Junebug Food Swans and Eggs Cat Eye Pupils Cob Web Origin Bee Sting Venom Appendix Function Stingrays Arm Pit Hair Function Deer Senses Tick Safety Palefaced Hornets and Risk Punnett Square Lettering Tick Types Hornet Behavior King Snakes Piercing Cartilidge American Kestrel Hawk Cottonmouths in Illinois Bees and flight Big Woodpeckers Crayfish Burrows June Bugs, Wasps and Hornets Waterdogs Moths and Metamorphosis Red Wasp Food Waterdogs Swan Eggs Dove Nesting Deer at Night Illinois Snakes Worm Teeth Housefly Napping Raising Ducks Scorpion Prevention Multiple Moths Young Birds

209

Microsoft Word - Agenda 071910.doc

Broader source: Energy.gov (indexed) [DOE]

Cybersecurity for Energy Delivery Systems Cybersecurity for Energy Delivery Systems 2010 Peer Review July 20-22, 2010 Westin Alexandria â— Alexandria, VA Tuesday, July 20 - Day 1 Time Activity Host/Presenter 7:30 - 8:30 am Registration and Continental Breakfast 8:30 - 8:45 am Welcome from Program Manager Carol Hawk 8:45 - 9:00 am Introductions and Instructions Katie Jereza Best Practices/Standards Development 9:00 - 9:30 am Advanced Security Acceleration Project for the Smart Grid (ASAP-SG) Oak Ridge National Laboratory 9:30 - 10:00 am Lemnos Interoperable Security EnerNex Corporation 10:00 - 10:30 am Trustworthy Wireless for Critical Infrastructure Sites Oak Ridge National Laboratory 10:30 - 11:00 am BREAK Best Practice Design/Configuration

210

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

August 5, 2011 August 5, 2011 10:30 - 11:30 AM Minutes Attendees: Tom McVeigh, Gregg Penn, Abdi Salehi, Pat Thomas, Herb Toor, Csaba Toth, Weyland Wong 1. ES&H News and Lessons Learned: * Accident Statistics - A review of LBNL accident statistics for June 2011 reveals several slip/trip/fall accidents, including: i. An administrator fell while walking across a parking lot, ii. A project manager tripped while walking up a wooden stairs, iii. A custodian sprained an ankle while stepping on the edge of a manhole cover, iv. A guest tripped over a fire hose that was stretched across a driveway. v. A research associate was startled by a hawk and fell off a sidewalk, vi. A writer/editor lost footing on a tapered curb near a bus stop, vii. A laborer lost footing on slippery concrete while cleaning a catch

211

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Iowa based Iowa based upon the simple prescriptive option of the 2012 IECC. It does not provide a guarantee for meeting the IECC. This guide is not designed to reflect the actual energy code, with amendments, if any, adopted in Iowa and does not, therefore, provide a guarantee for meeting the state energy code. For details on the energy code adopted by Iowa, including how it may differ from the IECC, please contact your local building code official. Additional copies of this guide are available on www.reca-codes.com. CLIMATE ZONE 6 Allamakee Clay Hancock Palo Alto Black Hawk Clayton Hardin Plymouth Bremer Delaware Howard Pocahontas Buchanan Dickinson Humboldt Sac Buena Vista Emmet Ida Sioux Butler Fayette Kossuth Webster Calhoun Floyd Lyon Winnebago Cerro Gordo Franklin

212

Organic thin film prehistory: looking towards solution phase aggregation |

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Organic thin film prehistory: looking towards solution phase aggregation Organic thin film prehistory: looking towards solution phase aggregation Wednesday, November 6, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Christopher Tassone, SSRL Polymer bulk heterojunction (BHJ) solar cells have attracted significant attention in industry and academia because of their potential for achieving large-area, light-weight, and flexible photovoltaic devices through cost-effective solution deposition techniques. These devices consist of a blend of an absorbing polymer and an electron accepting fullerene, the molecular packing and phase segregation of which heavily influence power conversion efficiency by effecting important processes such as exciton splitting, charge transport, and recombination. Understanding and utilization of molecular interactions to predicatively control the

213

Secretary Chu Speaks at Washington Post Live | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Chu Speaks at Washington Post Live Chu Speaks at Washington Post Live Secretary Chu Speaks at Washington Post Live November 3, 2011 - 9:12am Addthis Secretary Chu Secretary Chu Former Secretary of Energy Secretary Chu's remarks, as prepared for delivery, at the Washington Post Smart Energy Conference. Thank you, Mary [Jordan], for that kind introduction. While the focus of this conference is on the future of energy, I want to start with some lessons from America's past. On a windy day at Kitty Hawk on December 17, 1903, the Wright Brothers launched the world's first powered airplane to achieve human flight - and with it, a whole new industry. For the next several years, they led the world. What is less appreciated is that the United States lost the technology lead in airplanes by the beginning of World War I. Although the

214

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bees dying after a sting Bees dying after a sting Name: Mrs. Collins' class! Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A Question: My fourth grade class would like to know why do bees die after they sting someone? Does this happen to all types of bees? Replies: Tim, Bees, wasps, and ants all belong to the order _Hymenoptera_ and are the only insects with "stingers" which are really the ovipositors of adult females. Some species have stingers that are barbed and remain in the wound. I've heard that honey bees are the only ones that die after stinging you, but I could not confirm this in any reference. Jade Hawk Just to clarify a bit..... When the stinger or ovipositor is left, the insect has torn off a part of its abdomen and cannot survive the damage. Ric

215

Property:ProjectTechnology | Open Energy Information

ProjectTechnology ProjectTechnology Jump to: navigation, search Property Name ProjectTechnology Property Type Page Has Default form Marine and Hydrokinetic Technology Pages using the property "ProjectTechnology" Showing 25 pages using this property. (previous 25) (next 25) M MHK Projects/40MW Lewis project + MHK Technologies/Oyster + MHK Projects/ADM 3 + MHK Technologies/Wavebob + MHK Projects/ADM 4 + MHK Technologies/Wavebob + MHK Projects/AW Energy EMEC + MHK Technologies/Wave Roller + MHK Projects/Alaska 35 + MHK Technologies/Ocean +, MHK Technologies/Kensington + MHK Projects/BW2 Tidal + MHK Technologies/RED HAWK + MHK Projects/BioSTREAM Pilot Plant + MHK Technologies/bioSTREAM + MHK Projects/Bluemill Sound + MHK Technologies/Exim + MHK Projects/Bondurant Chute + MHK Technologies/SmarTurbine +

216

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Iowa. The requirements in the 2009 IECC Iowa. The requirements in the 2009 IECC are the same for windows used in new buildings, remodeling & additions to existing buildings, and as replacements of existing windows. Step-by-Step Instructions 1. Using the climate zone map or table, match the jurisdiction to the appropriate IECC climate zone. Use the "IECC Prescriptive Window Energy Efficiency Requirements" (on the back of this sheet) to determine the window performance requirements associated with the climate zone. 2. Construct the home with windows that have area weighted average U-factor and SHGC values less than or equal to the values for the climate zone and meet the code maximum air leakage requirements. IECC CLIMATE ZONE 6 Allamakee Clay Hancock Palo Alto Black Hawk Clayton Hardin Plymouth

217

Comparison of Three Ni-Hard I Alloys

Office of Scientific and Technical Information (OSTI)

Comparison of Three Ni-Hard I Alloys Comparison of Three Ni-Hard I Alloys Ã–. N. Do-an 1 , J.A. Hawk 1 , and J.Rice 2 1 U.S. Department of Energy, Albany Research Center, Albany, Oregon 2 Texaloy Foundry Co., Inc., Floresville, Texas Keywords: Ni-Hard white irons, Bainite, Martensite, Austenite, Abrasion resistant iron Abstract This report documents the results of an investigation which was undertaken to reveal the similarities and differences in the mechanical properties and microstructural characteristics of three Ni-Hard I alloys. One alloy (B1) is ASTM A532 class IA Ni-Hard containing 4.2 wt. pct. Ni. The second alloy (B2) is similar to B1 but higher in Cr, Si, and Mo. The third alloy (T1) also falls in the same ASTM specification, but it contains 3.3 wt. pct. Ni. The alloys were evaluated in both as-cast and

218

DOE Solar Decathlon: New Zealand: Victoria University of Wellington

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

New Zealand: Victoria University of Wellington New Zealand: Victoria University of Wellington Even before it was reassembled at West Potomac Park in Washington, D.C., Victoria University of Wellington's entry in the U.S. Department of Solar Decathlon 2011, First Light, had been sold at auction. However, the buyer's plans changed, and the house was offered for sale again. Today, First Light is settled in a stunning location in the seaside village of Waimarama, Hawkes Bay, New Zealand, and is available for rent as short-stay holiday accommodations. First Light was inspired by the traditional New Zealand holiday home-the "Kiwi bach," and it won third place overall in Solar Decathlon 2011. It placed first in the Engineering Contest and second in the Architecture Contest. It was also featured in Air New Zealand's inflight magazine, Kia

219

The Next Challenge in X-Ray Science: Control of Resonant Electronic

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The Next Challenge in X-Ray Science: Control of Resonant Electronic The Next Challenge in X-Ray Science: Control of Resonant Electronic Processes Wednesday, September 11, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Joachim StÃ¶hr, LCLS My talk will give a historic perspective of the revolutionary science that was enabled by the advent of high power sources of coherent electromagnetic radiation and the implications for future scientific opportunities with x-ray free electron lasers (X-FELs). The historical journey starts with the development of radar microwave sources in the 1940s that fueled the development of nuclear magnetic resonance (NMR) techniques which by now have led to 6 Nobel Prizes. The theoretical description of NMR as coherent processes between nuclear states by Rabi and Bloch also provided the theoretical basis for the optical laser and its applications. Over the last

220

NREL: News Feature - Middle Schoolers Shine in Electric Car Races

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Middle Schoolers Shine in Electric Car Races Middle Schoolers Shine in Electric Car Races May 24, 2013 In this photo, a boy grins widely as he holds a yellow folder over his model solar car. In the background are several black neoprene tracks and other middle-school students awaiting the starting signal. An adult race judge holds her hand in the air, signaling that everything is ready for the start of the race. Enlarge image Xavier Urquijo from Summit Ridge Middle School in Littleton waits for the start signal to lift the folder covering the solar panel on his team's car, "Knight Hawk." His team was one of 97 from 28 Colorado middle schools racing solar and lithium-ion powered vehicles they designed and built themselves at NREL's 2013 Junior Solar Sprint and Lithium-Ion Battery car competitions on May 18.

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

221

Secretary Chu Speaks at Washington Post Live | Department of Energy

Broader source: Energy.gov (indexed) [DOE]

Speaks at Washington Post Live Speaks at Washington Post Live Secretary Chu Speaks at Washington Post Live November 3, 2011 - 9:12am Addthis Secretary Chu Secretary Chu Former Secretary of Energy Secretary Chu's remarks, as prepared for delivery, at the Washington Post Smart Energy Conference. Thank you, Mary [Jordan], for that kind introduction. While the focus of this conference is on the future of energy, I want to start with some lessons from America's past. On a windy day at Kitty Hawk on December 17, 1903, the Wright Brothers launched the world's first powered airplane to achieve human flight - and with it, a whole new industry. For the next several years, they led the world. What is less appreciated is that the United States lost the technology lead in airplanes by the beginning of World War I. Although the

222

Energy Storage Systems 2010 Update Conference Presentations - Day 2,

Broader source: Energy.gov (indexed) [DOE]

3 3 Energy Storage Systems 2010 Update Conference Presentations - Day 2, Session 3 The U.S. DOE Energy Storage Systems Program (ESS) conducted a record-breaking Update Conference at the Washington DC Marriott Hotel on Nov. 2 - 4, 2010, with more than 500 attendees. The 2010 agenda reflected increased national interest in energy storage issues. The 3-day conference included 11 sessions plus a poster session on the final day. Presentations from the third session of Day 2, chaired by NETL's Ron Staubly, are below. ESS 2010 Update Conference - Detroit Edison's Advanced Implementatin of A123's Community ESS for Grid Support - Hawk Asgeirsson, DTE.pdf ESS 2010 Update Conference - Compressed Air Energy Storage (CAES) - Hal LaFlash, PG&E.pdf ESS 2010 Update Conference - Isothermal Compressed Air Energy Storage - Dax

223

Cyber Security Summer School: Lessons for the Modern Grid | Department of

Broader source: Energy.gov (indexed) [DOE]

Cyber Security Summer School: Lessons for the Modern Grid Cyber Security Summer School: Lessons for the Modern Grid Cyber Security Summer School: Lessons for the Modern Grid June 20, 2011 - 4:34pm Addthis Carol Hawk Program Manager, Cyber Security for Energy Delivery Systems What does this mean for me? Computer systems do more than store and share information. They help control our traffic lights, trains and specifically, our electric grid -- tasks for which continuous function is the primary concern. Protecting control systems on the grid from cyber attack requires a completely different approach to cyber security than information technology systems. The Cyber Summer School gave aspiring attendees a practical understanding of the connection between power systems and computer science required to secure a clean, reliable energy future.

224

Office of Legacy Management (LM)

-146 -146 I . . :, ~70-340 : .;, _. Spencer Chetnical Ccmpny &Q&t Building .:. /.: : Xensas City, Hiosouri .,i Attention: &.N~,~-l~ ~.I_ .z ,%;,.::.r .~'..; ,,., ,. : 1~. wt1-*: :,..: .,..' ..,,/ : f ,.,,. :;Lil~~.+ A,;; ;.,,I ~'~&:,.,3~ :;~ .: Thts refers to thr'iampactieo ckoducted.~~May 2 - 5, 1961, of activitiias at your~hawk~orlc8, Pfttsburg,~a;ansas, lic8msed under Source HaSerial Lieeme.Ho.C-4352 and Special Nuclear Material LiCans8 x011. 5xX-154 and a-329. ;. ; ., .,., :_: ,.,, .: : : .,. It appaars that certain of your ac&tiea were nit condkted & fgll canplian~e with a conditiw of a licenaa and.the raquiremeota of the AX's "Standard8 for Protection Against Radiation." Part20, Tit18 10, .cOd8 Of Fedetal %S&ationS, in. that:

225

Energy Storage Systems 2010 Update Conference Presentations - Day 2,

Broader source: Energy.gov (indexed) [DOE]

3 3 Energy Storage Systems 2010 Update Conference Presentations - Day 2, Session 3 The U.S. DOE Energy Storage Systems Program (ESS) conducted a record-breaking Update Conference at the Washington DC Marriott Hotel on Nov. 2 - 4, 2010, with more than 500 attendees. The 2010 agenda reflected increased national interest in energy storage issues. The 3-day conference included 11 sessions plus a poster session on the final day. Presentations from the third session of Day 2, chaired by NETL's Ron Staubly, are below. ESS 2010 Update Conference - Detroit Edison's Advanced Implementatin of A123's Community ESS for Grid Support - Hawk Asgeirsson, DTE.pdf ESS 2010 Update Conference - Compressed Air Energy Storage (CAES) - Hal LaFlash, PG&E.pdf ESS 2010 Update Conference - Isothermal Compressed Air Energy Storage - Dax

226

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Publications Hometown News Releases News Releases issued in: 2011, 2010, 2009, 2008 October 18, 2013 NETL Researcher Honored with 2013 Federal Laboratory Consortium Award Morgantown, W.Va. - Dr. Stephen E. Zitney of the National Energy Technology Laboratory (NETL) has been awarded a Mid-Atlantic region Federal Laboratory Consortium (FLC) award for Excellence in Technology Transfer for his work on the 3D Virtual Energy Plant Simulator and Immersive Training System. October 18, 2013 NETL Researcher Honored with 2013 Federal Laboratory Consortium Award Albany, Ore. - Jeffrey Hawk of the National Energy Technology Laboratory (NETL) has been awarded a Far West region Federal Laboratory Consortium (FLC) award for Outstanding Technology Development for his work on Superior Heat Resistant Alloys through Controlled Homogenization.

227

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Black Holes at RHIC? Black Holes at RHIC? Further discussion by Physicist Dmitri Kharzeev on why RHIC cannot produce a real gravitational black hole Black holes are among the most mysterious objects in the universe. The gravitational field of a black hole is so strong that Einstein's general relativity tells us that nothing, not even light, can escape from the black hole's interior. However, in 1974 physicist Stephen Hawking demonstrated that black holes must emit radiation once the quantum effects are included. According to quantum mechanics, the physical vacuum is bubbling with short-lived virtual particle-antiparticle pairs. Creation of a particle-antiparticle pair from the vacuum conflicts with energy conservation, but energy need not be conserved at short times in quantum mechanics, according to Heisenberg's

228

Water an Unusual Liquid; LCLS Provides New Insights | Stanford Synchrotron

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Water an Unusual Liquid; LCLS Provides New Insights Water an Unusual Liquid; LCLS Provides New Insights Wednesday, November 13, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Anders Nilsson, SUNCAT The anomalous physical properties of water are responsible for sustaining much of life on earth; for example, water displays a higher heat capacity than common liquids and expands upon freezing. Some of these anomalous physical properties become dramatically enhanced upon supercooling below the freezing point. In particular, extrapolations of the thermal expansion coefficient, isothermal compressibility, heat capacity and correlation length can all be fitted with a power law divergence with the same apparent singularity temperature of about 228 K. Experiments on pure bulk water below about ~240 K have so far been difficult: water crystallization occurs

229

Nevada's 2nd congressional district: Energy Resources | Open Energy

2nd congressional district: Energy Resources 2nd congressional district: Energy Resources Jump to: navigation, search Equivalent URI DBpedia This article is a stub. You can help OpenEI by expanding it. This page represents a congressional district in Nevada. Registered Energy Companies in Nevada's 2nd congressional district Arete Power Inc Biodiesel Solutions Inc BlackHawk Fund Brady Power Partners Chapeau Inc dba BluePoint Energy Inc China Recycling Energy Corp CREG Collier Technologies Inc Constellation Operating Services ElectraTherm Inc ElectraTherm, Inc. Empire Geothermal Power LLC Geothermal Development Associates Geothermal Technical Partners Gradient Resources Kodali Inc Lumenergi Magma Energy NV Energy Sierra Pacific Resources NV Energy formerly Sierra Pacific Power Newcore Energy Inc OHm Geothermal Ormat Funding Corp

230

Broader source: Energy.gov (indexed) [DOE]

th th Environmental Management Quality Assurance Corporate Board Meeting Minutes September 13, 2010 - Augusta, GA Page 1 of 13 Note: Revised by-laws for the EM QA Corporate Board were approved including the resolution of comments from the last meeting. The revised by-laws are posted at http://www.em.doe.gov/Pages/QACorporateBoard.aspx. Voting Board Members in Attendance (general attendance sheet for the meeting is attached): Brian Anderson - Idaho Brenda Hawks - Oak Ridge Ray Corey - Richland Jack Craig - Savannah River Bud Danielson -Chief of Nuclear Safety T.J. Jackson - EMCBC Steven Krahn (chair) - Headquarters EM-20 Jack Zimmerman - Portsmouth/Paducah Bob Murray (vice-chair) - Headquarters EM-23 No Voting Member Present - Carlsbad

231

Final_Tech_Session_Schedule_and_Location.xls

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Analysis of In-Situ Stress Regime in the Alberta Basin, Canada, for Performance Assessment of CO 2 Geological Sequestration Sites Christopher D. Hawkes, University of Saskatchewan, Stefan Bachu and Kristine Haug, Alberta Energy and Utilities Board, and Adam W. Thompson, University of Saskatchewan, Canada CONFERENCE PROCEEDINGS FOURTH ANNUAL CONFERENCE ON CARBON CAPTURE AND SEQUESTRATION DOE/NETL May 2-5, 2005 ABSTRACT Oil and gas reservoirs and deep saline aquifers are primary candidates for long-term geological sequestration of greenhouse and acid gases. Risk assessment for sequestration projects must include predictions of sequestration zone performance. These performance assessments will guide the selection of sequestration sites and/or operating parameters, such as injection pressure and rate, that mitigate

232

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Tough Times for the Muskrats Tough Times for the Muskrats Nature Bulletin No. 3 February 24, 1945 Forest Preserve District of Cook County Clayton F Smith, President Roberts Mann, Superintendent of Conservation TOUGH TIMES FOR THE MUSKRATS This has been a sorry year for the muskrats. The long drought, last summer and fall, dried up many of the smaller marshes and ponds where they had been living and forced them to migrate overland to new homes. Many undoubtedly were killed while enroute by mink, hawks, or dogs. Even the larger marshes and ponds were made smaller and more shallow by the drought and now this severe winter, with its long, bitter cold, has caused many of them to freeze solid to the very bottom; thus sealing the muskrats up in their lodges and preventing them from swimming around under the ice to get food.

233

Broader source: Energy.gov (indexed) [DOE]

Detroit Edison's Advanced Detroit Edison's Advanced Implementation of A123's Community Energy Storage Systems for Grid Support (DE-OE0000229) Hawk Asgeirsson Principal Investigator November 3, 2010 Funded in part by the Energy Storage Systems Program of the U.S. Department Of Energy through National Energy Technology Laboratory Community Energy Storage * The project is a proof of concept of an aggregated Community Energy Storage (CES) system in a utility territory; demonstrating the following capabilities: - Voltage/VAR Support - Integration renewable generation - Islanding during outages - Frequency Regulation * Demonstrate the application of secondary-use EV batteries as CES devices. Identifying alternative applications for EV type batteries may accelerate the reduction of cost for electric vehicle batteries.

234

For small values of the mass (in relation to the angular momentum and electric charge), the Kerr-Newman (KN) solution of Einstein equation reduces to a naked singularity of circular shape. By considering the Hawking and Ellis extended interpretation of the KN spacetime, as well as Wheeler's idea of "charge without charge", the non-trivial topological structure of the extended KN spatial section is found to represent gravitational states with half-integral angular momentum. As a consequence, it can be consistently interpreted as a model for the electron-positron system, in which the concepts of mass, charge and spin emerge from the spacetime geometry. According to this model, therefore, instead of a simple arena, spacetime must have a concrete existence, being responsible -- through its highly non-trivial topological structures -- for the building blocks of (at least some of) the existing matter in the universe.

H. I. Arcos; J. G. Pereira

2007-10-01T23:59:59.000Z

235

Wave blocking and partial transmission in subcritical flows over an obstacle

We study and measure the transmission coefficient of counter-propagating shallow-water waves produced by a wave generator and scattered by an obstacle. To precisely compare theoretical predictions and experimental data, we consider $\\sim 25$ frequencies for 5 subcritical background flows, where the maximum value of the Froude number ranges from $0.5$ to $0.75$. For each flow, the transmission coefficient displays a sharp transition separating total transmission from wave-blocking. Both the width and the central frequency of the transition are in good agreement with their theoretical values. The shape of the obstacle is identical to that used by the Vancouver team in the recent experiment aiming at detecting the analogue of stimulated Hawking radiation. Our results are compatible with the observations that have been reported. They complete them by establishing that the contribution of the transmission coefficient cannot be neglected for the lower half of the probed frequency range.

Léo-Paul Euvé; Florent Michel; Renaud Parentani; Germain Rousseaux

2015-02-06T23:59:59.000Z

236

Wave blocking and partial transmission in subcritical flows over an obstacle

We study and measure the transmission coefficient of counter-propagating shallow-water waves produced by a wave generator and scattered by an obstacle. To precisely compare theoretical predictions and experimental data, we consider $\\sim 25$ frequencies for 5 subcritical background flows, where the maximum value of the Froude number ranges from $0.5$ to $0.75$. For each flow, the transmission coefficient displays a sharp transition separating total transmission from wave-blocking. Both the width and the central frequency of the transition are in good agreement with their theoretical values. The shape of the obstacle is identical to that used by the Vancouver team in the recent experiment aiming at detecting the analogue of stimulated Hawking radiation. Our results are compatible with the observations that have been reported. They complete them by establishing that the contribution of the transmission coefficient cannot be neglected for the lower half of the probed frequency range.

Euvé, Léo-Paul; Parentani, Renaud; Rousseaux, Germain

2014-01-01T23:59:59.000Z

237

We present novel methods to numerically address the problem of characterizing the response of particle detectors in curved spacetimes. These methods allow for the integration of the Wightman function, at least in principle, in rather general backgrounds. In particular we will use this tool to further understand the nature of conformal massless scalar Hawking radiation from a Schwarzschild black hole in anti-de Sitter space. We do that by studying an Unruh-DeWitt detector at rest above the horizon and in circular geodesic orbit. The method allows us to see that the response rate shows peaks at certain characteristic frequencies, which correspond to the quasinormal modes (QNMs) of the space-time. It is in principle possible to apply these techniques to more complicated and interesting physical scenarios, e.g. geodesic infall or multiple detector entanglement evolution, or the study of the behaviour of quantum correlations in spacetimes with black hole horizons.

Keith K. Ng; Lee Hodgkinson; Jorma Louko; Robert B. Mann; Eduardo Martin-Martinez

2014-09-15T23:59:59.000Z

238

Northern goshawks (Accipiter gentilis) (hereafter referred to as goshawk) is a large forest dwelling hawk. Goshawks may be declining in population and reproduction in the southwestern United States. Reasons for the possible decline in goshawk populations include timber harvesting resulting in the loss of nesting habitat, toxic chemicals, and the effects of drought, fire, and disease. Thus, there is a need to determine their population status and assess impacts of management activities in potential goshawk habitat. Inventory for the goshawk was conducted on 2,254 ha of Los Alamos National Laboratory (LANL) to determine the presence of nesting goshawks on LANL lands. This information can be incorporated into LANL`s environmental management program. The inventory was conducted by Colorado State University personnel from May 12 to July 30, 1993. This report summarizes the results of this inventory.

Sinton, D.T.; Kennedy, P.L. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Fishery and Wildlife Biology

1994-06-01T23:59:59.000Z

239

Interactions between outgoing Hawking particles and ingoing matter are determined by gravitational forces and Standard Model interactions. In particular the gravitational interactions are responsible for the unitarity of the scattering against the horizon, as dictated by the holographic principle, but the Standard Model interactions also contribute, and understanding their effects is an important first step towards a complete understanding of the horizon's dynamics. The relation between in- and outgoing states is described in terms of an operator algebra. In this paper, the first of a series, we describe the algebra induced on the horizon by U(1) vector fields and scalar fields, including the case of an Englert-Brout-Higgs mechanism, and a more careful consideration of the transverse vector field components.

G. 't Hooft

2005-04-25T23:59:59.000Z

240

Uniformly accelerated black holes

Science Journals Connector (OSTI)

The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.

Patricio S. Letelier and Samuel R. Oliveira

2001-08-24T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

241

High intense electromagnetic fields can be unique probes to study natures of macroscopic vacua by themselves. Combining accelerators with the intense field can provide more fruitful probes which can neither be achieved by only intense fields nor only high energy accelerators. We will overview the natures of vacua which can be accessible via intense laser-laser and intense laser-electron interactions. In the case of the laser-laser interaction, we propose how to observe nonlinear QED effects and effects of new fields like light scalar and pseudo scalar fields which may contribute to a macroscopic nature of our universe such as dark energy. In the case of the laser-electron interaction, in addition to nonlinear QED effects, we can further discuss the nature of accelerating field in the vacuum where we can access physics related with event horizons such as Hawking-Unruh radiations. We will introduce a recent experimental trial to search for this kind of odd radiations.

Kensuke Homma

2009-11-30T23:59:59.000Z

242

Numerical investigation of the effect of chevrons in subsonic jets using URANS

Science Journals Connector (OSTI)

Numerical simulations of compressible, turbulent jets at M = 0.75 using the Shear Stress Transport (SST) k-? model have been carried out for baseline nozzle and chevron nozzles with 4, 6 and 8 lobes and three different penetration angles (0°, 5° and 10°). The predicted far field noise level at several observer locations are compared with experimental data. Overall sound pressure levels at far field observer locations have been calculated using Ffowcs Williams-Hawkings equation. Numerical prediction of aerodynamic quantities like centreline velocity, stagnation pressure, turbulent kinetic energy and axial vorticity are compared among the nozzles. The Unsteady Reynolds Averaged Navier Stokes (URANS) calculations are able to predict the trends in overall SPL, even though the absolute values are slightly under-predicted.

P.S. Tide; V. Babu

2010-01-01T23:59:59.000Z

243

Non-extremal fuzzballs and ergoregion emission

In the traditional picture of black holes Hawking radiation is created by pair creation from the vacuum at the horizon. In the fuzzball proposal, individual microstates do not have a horizon with the `vacuum' state in its vicinity. For a special family of non-extremal microstates it was recently found that emission occurs due to pair creation in an ergoregion, rather than at a horizon. In this paper we extend this result to a slightly larger class of microstates, again finding exact agreement between the emission in the gravity picture and the CFT dual. We write down an expression for emission from geometries with ergoregions, in terms of the leading falloff behavior of the wavefunctions in the fuzzball region. Finally, we describe another family of nonextremal microstates and find their ergoregion.

Borun D. Chowdhury; Samir D. Mathur

2008-10-23T23:59:59.000Z

244

Gödel black hole, closed timelike horizon, and the study of particle emissions

We show that a particle, with positive orbital angular momentum, following an outgoing null/timelike geodesic, shall never reach the closed timelike horizon (CTH) present in the $(4+1)$-dimensional rotating G\\"{o}del black hole space-time. Therefore a large part of this space-time remains inaccessible to a large class of geodesic observers, depending on the conserved quantities associated with them. We discuss how this fact and the existence of the closed timelike curves present in the asymptotic region make the quantum field theoretic study of the Hawking radiation, where the asymptotic observer states are a pre-requisite, unclear. However, the semiclassical approach provides an alternative to verify the Smarr formula derived recently for the rotating G\\"{o}del black hole. We present a systematic analysis of particle emissions, specifically for scalars, charged Dirac spinors and vectors, from this black hole via the semiclassical complex path method.

Sourav Bhattacharya; Anirban Saha

2010-07-22T23:59:59.000Z

245

Coarse-grained entropy and causal holographic information in AdS/CFT

We propose bulk duals for certain coarse-grained entropies of boundary regions. The `one-point entropy' is defined in the conformal field theory by maximizing the entropy in a domain of dependence while fixing the one-point functions. We conjecture that this is dual to the area of the edge of the region causally accessible to the domain of dependence (i.e. the `causal holographic information' of Hubeny and Rangamani). The `future one-point entropy' is defined by generalizing this conjecture to future domains of dependence and their corresponding bulk regions. We show that the future one-point entropy obeys a nontrivial second law. If our conjecture is true, this answers the question "What is the field theory dual of Hawking's area theorem?"

William R. Kelly; Aron C. Wall

2014-04-01T23:59:59.000Z

246

The use of accelerated radiation testing for avionics

Science Journals Connector (OSTI)

In recent years the use of unmanned aerial vehicles (UAVs) for military and national security applications has been increasing. One possible use of these vehicles is as remote sensing platforms where the UAV carries several sensors to provide real-time information about biological chemical or radiological agents that might have been released into the environment. One such UAV the Global Hawk has a payload space that can carry nearly one ton of sensing equipment which makes these platforms significantly larger than many satellites. Given the size of the potential payload and the heightened radiation environment at high altitudes these systems could be affected by the radiation-induced failure mechanisms from the naturally occurring terrestrial environment. In this paper we will explore the use of accelerated radiation testing to prepare UAV payloads for deployment.

2013-01-01T23:59:59.000Z

247

Recovering information of tunneling spectrum from Weakly Isolated Horizon

In this paper we investigate the properties of tunneling spectrum from weakly isolated horizon(WIH). We find that there are correlations among Hawking radiations from weakly isolated horizon, the information can be carried out in terms of correlations between sequential emissions, and the radiation is an entropy conservation process. We generalize Refs.[11-13]' results to a more general spacetime. Through revisiting the calculation of tunneling spectrum of weakly isolated horizon, we find that Ref.[12]'s requirement that radiating particles have the same angular momenta of unit mass as that of black hole is not needed, and the energy and angular momenta of emitting particles are very arbitrary which should be restricted only by keeping the cosmic censorship of black hole.

Ge-Rui Chen; Yong-Chang Huang

2014-06-02T23:59:59.000Z

248

Holographic screens in ultraviolet self-complete quantum gravity

In this paper we study the geometry and the thermodynamics of a holographic screen in the framework of the ultraviolet self-complete quantum gravity. To achieve this goal we construct a new static, neutral, non-rotating black hole metric, whose outer (event) horizon coincides with the surface of the screen. The space-time admits an extremal configuration corresponding to the minimal holographic screen and having both mass and radius equalling the Planck units. We identify this object as the space-time fundamental building block, whose interior is physically unaccessible and cannot be probed even during the Hawking evaporation terminal phase. In agreement with the holographic principle, relevant processes take place on the screen surface. The area quantization leads to a discrete mass spectrum. An analysis of the entropy shows that the minimal holographic screen can store only one byte of information while in the thermodynamic limit the area law is corrected by a logarithmic term.

Piero Nicolini; Euro Spallucci

2014-03-04T23:59:59.000Z

249

NEAR-INFRARED PROPERTIES OF THE X-RAY-EMITTING YOUNG STELLAR OBJECTS IN THE CARINA NEBULA

The Great Nebula in Carina (NGC 3372) is the best target to study in detail the process of violent massive star formation and the resulting feedback effects of cloud dispersal and triggered star formation. While the population of massive stars is rather well studied, the associated low-mass stellar population was largely unknown up to now. The near-infrared study in this paper builds on the results of the Chandra Carina Complex Project, that detected 14,368 X-ray sources in the 1.4 deg{sup 2} survey region, an automatic source classification study that classified 10,714 of these X-ray sources as very likely young stars in Carina, and an analysis of the clustering properties of the X-ray-selected Carina members. In order to determine physical properties of the X-ray-selected stars, most of which were previously unstudied, we used HAWK-I at the ESO Very Large Telescope to conduct a very deep near-IR survey with subarcsecond angular resolution, covering an area of about 1280 arcmin{sup 2}. The HAWK-I images reveal more than 600,000 individual infrared sources, whereby objects as faint as J {approx} 23, H {approx} 22, and K{sub s} {approx} 21 are detected at signal-to-noise ratio (S/N) {>=}3. While less than half of the Chandra X-ray sources have counterparts in the Two Micron All Sky Survey catalog, the {approx}5 mag deeper HAWK-I data reveal infrared counterparts to 6636 (=88.8%) of the 7472 Chandra X-ray sources in the HAWK-I field. We analyze near-infrared color-color and color-magnitude diagrams to derive information about the extinctions, infrared excesses (as tracers for circumstellar disks), ages, and masses of the X-ray-selected objects. The near-infrared properties agree well with the results of the automatic X-ray source classification, showing that the remaining contamination in the X-ray-selected sample of Carina members is very low ({approx}<7%). The shape of the K-band luminosity function of the X-ray-selected Carina members agrees well with that derived for the Orion Nebula Cluster, suggesting that, down to the X-ray detection limit around 0.5-1 M{sub sun}, the shape of the initial mass function (IMF) in Carina is consistent with that in Orion (and thus the field IMF). The fraction of stars with near-infrared excesses is rather small, {approx}<10%, but shows considerable variations between individual parts of the complex. The distribution of extinctions for the diskless stars ranges from {approx}1.6 mag to {approx}6.2 mag (central 80th percentile), clearly showing a considerable range of differential extinction between individual stars in the complex.

Preibisch, Thomas [Universitaets-Sternwarte Muenchen, Ludwig-Maximilians-Universitaet, Scheinerstr. 1, 81679 Muenchen (Germany); Hodgkin, Simon; Irwin, Mike; Lewis, James R. [Cambridge Astronomical Survey Unit, Institute of Astronomy, Madingley Road, Cambridge CB3 0HA (United Kingdom); King, Robert R. [Astrophysics Group, College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QL (United Kingdom); McCaughrean, Mark J. [European Space Agency, Research and Scientific Support Department, ESTEC, Postbus 299, 2200 AG Noordwijk (Netherlands); Zinnecker, Hans [Deutsches SOFIA Institut, Universitaet Stuttgart, Pfaffenwaldring 31, 70569 Stuttgart (Germany); Townsley, Leisa; Broos, Patrick [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park PA 16802 (United States)

2011-05-01T23:59:59.000Z

250

Lens spaces in the Regge calculus approach to quantum cosmology

Science Journals Connector (OSTI)

We study the wave function for a universe which is topologically a lens space within the Regge calculus approach. By restricting the four-dimensional simplicial complex to be a cone over the boundary lens space, described by a single internal edge length, and a single boundary edge length, one can analyze in detail the analytic properties of the action in the space of complex edge lengths. The classical extrema and convergent steepest descent contours of integration yielding the wave function are found. Both the Hartle-Hawking- and Linde-Vilenkin-type proposals are examined and, in all cases, we find wave functions which predict a Lorentzian oscillatory behavior in the late universe. The behavior of the results under subdivision of the boundary universe is also presented.

Danny Birmingham

1995-11-15T23:59:59.000Z

251

Wave blocking and partial transmission in subcritical flows over an obstacle

We study and measure the transmission coefficient of counter-propagating shallow-water waves produced by a wave generator and scattered by an obstacle. To precisely compare theoretical predictions and experimental data, we consider $\\sim 25$ frequencies for 5 subcritical background flows, where the maximum value of the Froude number ranges from $0.5$ to $0.75$. For each flow, the transmission coefficient displays a sharp transition separating total transmission from wave-blocking. Both the width and the central frequency of the transition are in good agreement with their theoretical values. The shape of the obstacle is identical to that used by the Vancouver team in the recent experiment aiming at detecting the analogue of stimulated Hawking radiation. Our results are compatible with the observations that have been reported. They complete them by establishing that the contribution of the transmission coefficient cannot be neglected for the lower half of the probed frequency range.

Léo-Paul Euvé; Florent Michel; Renaud Parentani; Germain Rousseaux

2014-09-12T23:59:59.000Z

252

Lorentz violation and perpetual motion

We show that any Lorentz violating theory with two or more propagation speeds is in conflict with the generalized second law of black hole thermodynamics. We do this by identifying a classical energy-extraction method, analogous to the Penrose process, which would decrease the black hole entropy. Although the usual definitions of black hole entropy are ambiguous in this context, we require only very mild assumptions about its dependence on the mass. This extends the result found by Dubovsky and Sibiryakov, which uses the Hawking effect and applies only if the fields with different propagation speeds interact just through gravity. We also point out instabilities that could interfere with their black hole {\\it perpetuum mobile}, but argue that these can be neglected if the black hole mass is sufficiently large.

Christopher Eling; Brendan Z. Foster; Ted Jacobson; Aron C. Wall

2007-05-25T23:59:59.000Z

253

Greybody factors in a rotating black-hole background: Fermions and gauge bosons

Science Journals Connector (OSTI)

We study the emission of fermion and gauge boson degrees of freedom on the brane by a rotating higher-dimensional black hole. Using matching techniques, for the near-horizon and far-field regime solutions, we solve analytically the corresponding field equations of motion. From this, we derive analytical results for the absorption probabilities and Hawking radiation emission rates, in the low-energy and low-rotation case, for both species of fields. We produce plots of these, comparing them to existing exact numerical results with very good agreement. We also study the total absorption cross section and demonstrate that, as in the nonrotating case, it has a different behavior for fermions and gauge bosons in the low-energy limit, while it follows a universal behavior—reaching a constant, spin-independent, asymptotic value—in the high-energy regime.

S. Creek, O. Efthimiou, P. Kanti, and K. Tamvakis

2007-11-09T23:59:59.000Z

254

Black Holes in the Cosmos, the Lab, and in Fundamental Physics (1/3)

Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

None

2011-10-06T23:59:59.000Z

255

Black Holes in the Cosmos, the Lab, and in Fundamental Physics (3/3)

Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

None

2011-10-06T23:59:59.000Z

256

Superradiance is a radiation enhancement process that involves dissipative systems. With a 60 year-old history, superradiance has played a prominent role in optics, quantum mechanics and especially in relativity and astrophysics. In General Relativity, black-hole superradiance is permitted by dissipation at the event horizon, that allows for energy and angular momentum extraction from the vacuum, even at the classical level. Black-hole superradiance is intimately connected to the black-hole area theorem, Penrose process, tidal forces and even Hawking radiation, which can be interpreted as a quantum version of black-hole superradiance. Various mechanisms (as diverse as massive fields, magnetic fields, anti-de Sitter boundaries, nonlinear interactions, etc...) can confine the amplified radiation and give rise to strong instabilities. These "black-hole bombs" have applications in searches of dark matter and of physics beyond the Standard Model, are associated to the threshold of formation of new black hole solut...

Brito, Richard; Pani, Paolo

2015-01-01T23:59:59.000Z

257

This paper reports that the United States delivered some US $11 billion of military hardware to Iran between 1969 and 1979, in the hopes of helping stabilize a volatile situation in the Middle East. That did not work. When Iran used the weapons against Iraq, the USSR, France, and a number of developing countries helped arm Iraq. It was this vast arsenal that Iraq deployed in its Kuwait-Persian Gulf War venture. Granted, those weapons were augmented by some U.S.-made equipment like TOW antitank missiles and Hawk antiaircraft missiles that were captured in the Iraqi attack on Kuwait. A report issued by the U.S. Office of Technology Assessment (OTA) in June cited that chain of events to demonstrate that the U.S. and other major exporters are gradually losing control of the weapons transferred (to other countries) as well as the technology and industry necessary to produce and support them.

Christiansen, D.

1991-09-01T23:59:59.000Z

258

Bonneville Power Administration (BPA) proposes to fund wildlife management and enhancement activities for the Burlington bottoms wetlands mitigation site. Acquired by BPA in 1991, wildlife habitat at Burlington bottoms would contribute toward the goal of mitigation for wildlife losses and inundation of wildlife habitat due to the construction of Federal dams in the lower Columbia and Willamette River Basins. Target wildlife species identified for mitigation purposes are yellow warbler, great blue heron, black-capped chickadee, red-tailed hawk, valley quail, spotted sandpiper, wood duck, and beaver. The Draft Management Plan/Environmental Assessment (EA) describes alternatives for managing the Burlington Bottoms area, and evaluates the potential environmental impacts of the alternatives. Included in the Draft Management Plan/EA is an implementation schedule, and a monitoring and evaluation program, both of which are subject to further review pending determination of final ownership of the Burlington Bottoms property.

Not Available

1994-12-01T23:59:59.000Z

259

Corrected form of the first law of thermodynamics for regular black holes

We show by explicit computations that there is a superficial inconsistency between the conventional first law of black hole thermodynamics and Bekenstein-Hawking area law for three types of regular black holes. The corrected form of the first law for these regular black holes is given. The derivation relies on the general structure of the energy-momentum tensor of the matter fields. When the black hole mass parameter $M$ is included in the energy-momentum tensor, the conventional form of the first law should be modified with an extra factor. In this case, the black hole mass $M$ can no longer be considered as the internal energy of the regular black holes.

Meng-Sen Ma; Ren Zhao

2014-11-04T23:59:59.000Z

260

Quantum gravity effects in the Kerr spacetime

We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the 'dressing' of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity.

Reuter, M. [Institute of Physics, University of Mainz, Staudingerweg 7, D-55099 Mainz (Germany); Tuiran, E. [Departamento de Fisica, Universidad del Norte, Km 5 via a Puerto Colombia, AA-1569 Barranquilla (Colombia)

2011-02-15T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

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261

We study the AdS/CFT thermodynamics of the spatially isotropic counterpart of the Bjorken similarity flow in d-dimensional Minkowski space with d{>=}3, and of its generalization to linearly expanding d-dimensional Friedmann-Robertson-Walker cosmologies with arbitrary values of the spatial curvature parameter k. The bulk solution is a nonstatic foliation of the generalized Schwarzschild-AdS black hole with a horizon of constant curvature k. The boundary matter is an expanding perfect fluid that satisfies the first law of thermodynamics for all values of the temperature and the spatial curvature, but it admits a description as a scale-invariant fluid in local thermal equilibrium only when the inverse Hawking temperature is negligible compared with the spatial curvature length scale. A Casimir-type term in the holographic energy-momentum tensor is identified from the threshold of black hole formation and is shown to take different forms for k{>=}0 and k<0.

Kajantie, K. [Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Department of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Louko, Jorma [School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Tahkokallio, T. [Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Department of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia, V8W 3P6 (Canada)

2008-12-15T23:59:59.000Z

262

The generalized second law of thermodynamics and the nature of the Entropy Function

In black hole physics, the second law of thermodynamics is generally valid whether the black hole is a static or a non-static one. Considering the universe as a thermodynamical system the second law of black hole dynamics extends to the non-negativity of the sum of the entropy of the matter and the horizon, known as generalized second law of thermodynamics(GSLT). Here, we have assumed the universe to be bounded by the event-horizon where Bekenstein entropy-area relation and Hawking-temperature are not applicable. Thus considering entropy to be an arbitrary function of the area of the event-horizon, we have tried to find the nature of the entropy-function for the validity of the GSLT both in quintessence-era and in phantom-era. Finally, some graphical representation of the entropy-function has been presented.

Subenoy Chakraborty; Nairwita Mazumder; Ritabrata Biswas

2010-09-15T23:59:59.000Z

263

General first law and thermodynamics of horizon/matter systems

Science Journals Connector (OSTI)

The first law of thermodynamics is derived for bounded, static, spherically symmetric spacetimes which include a matter distribution and either a black-hole or cosmological horizon. Heat capacities associated with horizon/matter systems are calculated. It is found that if the surface area of the boundary is held fixed, the heat capacity of a system including a black hole can always be made positive by including a matter distribution of sufficient density. The heat capacity associated with a system including a cosmological horizon and a matter distribution may be positive or negative depending on the matter configuration, but must always be negative in the limit that the boundary approaches the horizon. A discussion is given of the case in which the cosmological constant is allowed to vary. It is found that the Hawking-Coleman mechanisms for explaining the low value of the cosmological constant are not well defined.

G. Hayward

1991-06-15T23:59:59.000Z

264

Corrected form of the first law of thermodynamics for regular black holes

We show by explicit computations that there is a superficial inconsistency between the conventional first law of black hole thermodynamics and Bekenstein-Hawking area law for three types of regular black holes. The corrected form of the first law for these regular black holes is given. The derivation relies on the general structure of the energy-momentum tensor of the matter fields. When the black hole mass parameter $M$ is included in the energy-momentum tensor, the conventional form of the first law should be modified with an extra factor. In this case, the black hole mass $M$ can no longer be considered as the internal energy of the regular black holes.

Ma, Meng-Sen

2014-01-01T23:59:59.000Z

265

Fermion Absorption Cross Section and Topology of Spherically Symmetric Black Holes

In 1997, Liberati and Pollifrone in Phys. Rev. D56 (1997) 6458 (hep-th/9708014) achieved a new formulation of the Bekenstein-Hawking formula, where the entropy and the Euler characteristic are related by $S=\\chi A/8$. In this work we present a relation between the low-energy absorption cross section for minimally coupled fermions and the Euler characteristic of (3+1)-dimensional spherically symmetric black holes, i.e. $\\sigma =\\chi g_h^{-1}A$. Based on the relation, using the Gauss--Bonnet--Chern theorem and the $\\phi$-mapping method, an absorption cross section density is introduced to describe the topology of the absorption cross section. It is shown that the absorption cross section and its density are determined by the singularities of the timelike Killing vector field of the spacetime and these singularities carry the topological numbers, Hopf indices and Brouwer degrees, naturally.

Yu-Xiao Liu; Li Zhao; Zhen-Bin Cao; Yi-Shi Duan

2007-02-18T23:59:59.000Z

266

On the temperature dependence of the absorption cross section for charged black holes

We analyze the the low frequency absorption cross section of minimally coupled massless scalar fields by different kinds of charged static black holes, namely the d-dimensional Reissner-Nordstrom solution, the D1-D5 system in d=5 and a four dimensional dyonic four-charged black hole. In each case we show that this cross section is inversely proportional to the black hole Hawking temperature. This inverse proportionality also arises in the same cross section for black holes with string $alpha' corrections, as we have shown in a previous work: string corrections induce such temperature dependence. In each case we also carefully analyze the extremal limit and show that the cross section is well defined in it.

Filipe Moura

2014-06-08T23:59:59.000Z

267

Relaxation jumps of strong vibration

Science Journals Connector (OSTI)

A nonperturbative theory of two-phonon relaxation of a strongly excited local mode is developed, whereby the mode is considered classically and phonons, quantum mechanically. The relaxation mechanism is analogous to that of black hole emission proposed by Hawking: it consists of linear transformation of phonon operators in time, which is induced by the classical subsystem (mode). Due to this transformation the number of phonons increases while the energy of the local mode decreases in time. It is found that there exist some critical energies of the local mode when relaxation rate is strongly enhanced. Thereby relaxation jumps take place, which are accompanied by generation of bursts of phonons. The values of the critical energies do not depend on temperature. The final stage of relaxation is exponential, in agreement with perturbation theory. Numerical calculations of the relaxation jumps are presented.

V. Hizhnyakov

1996-06-01T23:59:59.000Z

268

Vacuum energy and the latent heat of AdS-Kerr black holes

Phase transitions for rotating asymptotically anti-de Sitter black holes in four dimensions are described in the $P-T$ plane, in terms of the Hawking temperature and the pressure provided by the cosmological constant. The difference between constant angular momentum and constant angular velocity is highlighted, the former has a second order phase transition while the latter does not. If the angular momentum is fixed there a line of first order phase transitions terminating at a critical point with a second order phase transition and vanishing latent heat, while if the angular velocity is fixed there is a line of first order phase transitions terminating at a critical point with infinite latent heat. For constant angular velocity the analytic form of the phase boundary is determined, latent heats derived and the Clapeyron equation verified.

Brian P. Dolan

2014-07-15T23:59:59.000Z

269

In these two lectures, we will address the topic of the creation of small black holes during particle collisions in a ground-based accelerator, such as LHC, in the context of a higher-dimensional theory. We will cover the main assumptions, criteria and estimates for their creation, and we will discuss their properties after their formation. The most important observable effect associated with their creation is likely to be the emission of Hawking radiation during their evaporation process. After presenting the mathematical formalism for its study, we will review the current results for the emission of particles both on the brane and in the bulk. We will finish with a discussion of the methodology that will be used to study these spectra, and the observable signatures that will help us identify the black-hole events.

Panagiota Kanti

2008-02-15T23:59:59.000Z

270

Black Holes in the Cosmos, the Lab, and in Fundamental Physics (2/3)

Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.

None

2011-10-06T23:59:59.000Z

271

Relativeness in Quantum Gravity: Limitations and Frame Dependence of Semiclassical Descriptions

Consistency between quantum mechanical and general relativistic views of the world is a longstanding problem, which becomes particularly prominent in black hole physics. We develop a coherent picture addressing this issue by studying the quantum mechanics of an evolving black hole. After interpreting the Bekenstein-Hawking entropy as the entropy representing the degrees of freedom that are coarse-grained to obtain a semiclassical description from the microscopic theory of quantum gravity, we discuss the properties these degrees of freedom exhibit when viewed from the semiclassical standpoint. We are led to the conclusion that they show features which we call extreme relativeness and spacetime-matter duality---a nontrivial reference frame dependence of their spacetime distribution and the dual roles they play as the "constituents" of spacetime and as thermal radiation. We describe black hole formation and evaporation processes in distant and infalling reference frames, showing that these two properties allow u...

Nomura, Yasunori; Weinberg, Sean J

2014-01-01T23:59:59.000Z

272

Particle detectors in curved spacetime quantum field theory

Unruh-DeWitt particle detector models are studied in a variety of time-dependent and time-independent settings. We work within the framework of first-order perturbation theory and couple the detector to a massless scalar field. The necessity of switching on (off) the detector smoothly is emphasised throughout, and the transition rate is found by taking the sharp-switching limit of the regulator-free and finite response function. The detector is analysed on a variety of spacetimes: $d$-dimensional Minkowski, the Ba\\~nados-Teitelboim-Zanelli (BTZ) black hole, the two-dimensional Minkowski half-plane, two-dimensional Minkowski with a receding mirror, and the two- and four-dimensional Schwarzschild black holes. In $d$-dimensional Minkowski spacetime, the transition rate is found to be finite up to dimension five. In dimension six, the transition rate diverges unless the detector is on a trajectory of constant proper acceleration, and the implications of this divergence to the global embedding spacetime (GEMS) methods are studied. In three-dimensional curved spacetime, the transition rate for the scalar field in an arbitrary Hadamard state is found to be finite and regulator-free. Then on the Ba\\~nados-Teitelboim-Zanelli (BTZ) black hole spacetime, we analyse the detector coupled to the field in the Hartle-Hawking vacua, under both transparent and reflective boundary conditions at infinity. Results are presented for the co-rotating detector, which responds thermally, and for the radially-infalling detector. In four-dimensional Schwarzschild spacetime, we proceed numerically, and the Hartle-Hawking, Boulware and Unruh vacua rates are compared. Results are presented for the case of the static detectors, which respond thermally, and also for the case of co-rotating detectors.

Lee Hodgkinson

2013-09-27T23:59:59.000Z

273

Recently, the Banados-Teitelboim-Zanelli (BTZ) black hole in the presence of the gravitational Chern-Simons term has been studied, and it is found that the usual thermodynamic quantities, like the black hole mass, angular momentum, and entropy, are modified. But, for large values of the gravitational Chern-Simons coupling where the modification terms dominate the original terms some exotic behaviors occur, like the roles of the mass and angular momentum are interchanged and the entropy depends more on the inner horizon area than the outer one. A basic physical problem of this system is that the form of entropy does not guarantee the second law of thermodynamics, in contrast to the Bekenstein-Hawking entropy. Moreover, this entropy does not agree with the statistical entropy, in contrast to a good agreement for small values of the gravitational Chern-Simons coupling. Here I find that there is another entropy formula where the usual Bekenstein-Hawking form dominates the inner-horizon term again, as in the small gravitational Chern-Simons coupling case, such that the second law of thermodynamics can be guaranteed. I also find that the new entropy formula agrees with the statistical entropy based on the holographic anomalies for the whole range of the gravitational Chern-Simons coupling. This reproduces, in the limit of a vanishing Einstein-Hilbert term, the recent result about the exotic BTZ black holes, where their masses and angular momenta are completely interchanged and the entropies depend only on the area of the inner horizon. I compare the result of the holographic approach with the classical-symmetry-algebra-based approach, and I find exact agreements even with the higher-derivative corrections of the gravitational Chern-Simons term. This provides a nontrivial check of the AdS/CFT correspondence, in the presence of higher-derivative terms in the gravity action.

Park, Mu-In [Center for Quantum Spacetime, Sogang University, Seoul 121-742 (Korea, Republic of)

2008-01-15T23:59:59.000Z

274

In this paper we extend the investigation of Adami and Ver Steeg [Class. Quantum Grav. \\textbf{31}, 075015 (2014)] to treat the process of black hole particle emission effectively as the analogous quantum optical process of parametric down conversion (PDC) with a dynamical (depleted vs. non-depleted) `pump' source mode which models the evaporating black hole (BH) energy degree of freedom. We investigate both the short time (non-depleted pump) and long time (depleted pump) regimes of the quantum state and its impact on the Holevo channel capacity for communicating information from the far past to the far future in the presence of Hawking radiation. The new feature introduced in this work is the coupling of the emitted Hawking radiation modes through the common black hole `source pump' mode which phenomenologically represents a quantized energy degree of freedom of the gravitational field. This (zero-dimensional) model serves as a simplified arena to explore BH particle production/evaporation and back-action effects under an explicitly unitary evolution which enforces quantized energy/particle conservation. Within our analogous quantum optical model we examine the entanglement between two emitted particle/anti-particle and anti-particle/particle pairs coupled via the black hole (BH) evaporating `pump' source. We also analytically and dynamically verify the `Page information time' for our model which refers to the conventionally held belief that the information in the BH radiation becomes significant after the black hole has evaporated half its initial energy into the outgoing radiation. Lastly, we investigate the effect of BH particle production/evaporation on two modes in the exterior region of the BH event horizon that are initially maximally entangled, when one mode falls inward and interacts with the black hole, and the other remains forever outside and non-interacting.

Paul M. Alsing

2015-02-04T23:59:59.000Z

275

3D CFD Model of High Temperature H2O/CO2 Co-electrolysis

3D CFD Model of High Temperature H2O/CO2 Co-Electrolysis Grant Hawkes1, James O’Brien1, Carl Stoots1, Stephen Herring1 Joe Hartvigsen2 1 Idaho National Laboratory, Idaho Falls, Idaho, grant.hawkes@inl.gov 2 Ceramatec Inc, Salt Lake City, Utah INTRODUCTION A three-dimensional computational fluid dynamics (CFD) model has been created to model high temperature co-electrolysis of steam and carbon dioxide in a planar solid oxide electrolyzer (SOE) using solid oxide fuel cell technology. A research program is under way at the Idaho National Laboratory (INL) to simultaneously address the research and scale-up issues associated with the implementation of planar solid-oxide electrolysis cell technology for syn-gas production from CO2 and steam. Various runs have been performed under different run conditions to help assess the performance of the SOE. This paper presents CFD results of this model compared with experimental results. The Idaho National Laboratory (INL), in conjunction with Ceramatec Inc. (Salt Lake City, USA) has been researching for several years the use of solid-oxide fuel cell technology to electrolyze steam for large-scale nuclear-powered hydrogen production. Now, an experimental research project is underway at the INL to produce syngas by simultaneously electrolyzing at high-temperature steam and carbon dioxide (CO2) using solid oxide fuel cell technology. A strong interest exists in the large-scale production of syn-gas from CO2 and steam to be reformed into a usable transportation fuel. If biomass is used as the carbon source, the overall process is climate neutral. Consequently, there is a high level of interest in production of syn-gas from CO2 and steam electrolysis. With the price of oil currently around $60 / barrel, synthetically-derived hydrocarbon fuels (synfuels) have become economical. Synfuels are typically produced from syngas – hydrogen (H2) and carbon monoxide (CO) -- using the Fischer-Tropsch process, discovered by Germany before World War II. High-temperature nuclear reactors have the potential for substantially increasing the efficiency of syn-gas production from CO2 and water, with no consumption of fossil fuels, and no production of greenhouse gases. Thermal CO2-splitting and water splitting for syn-gas production can be accomplished via high-temperature electrolysis, using high-temperature nuclear process heat and electricity. A high-temperature advanced nuclear reactor coupled with a high-efficiency high-temperature electrolyzer could achieve a competitive thermal-to-syn-gas conversion efficiency of 45 to 55%.

Grant Hawkes; James O'Brien; Carl Stoots; Stephen Herring; Joe Hartvigsen

2007-06-01T23:59:59.000Z

276

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Toad Toad Nature Bulletin No. 158 June 5, 1948 Forest Preserve District of Cook County William N. Erickson, President Roberts Mann, Supt. of Conservation THE TOAD The toad, distinguished by its wide heavy body, dry warty skin and a large kidney-shaped gland on each shoulder, is a most interesting and valuable animal. There are many superstitions about this gentle harmless amphibian so loathed by many people. It is not evil or venomous; it does not "rain down" from the sky; it cannot exist for centuries sealed in the heart of a tree or solid rock; it does not cause warts. From those two big glands and from the "warts", which are also glands, a toad can secrete a milky fluid which is harmless to man but which makes it distasteful to most animals. However, they are eaten by most large snakes and by many hawks, owls, herons and bitterns. Because its food is chiefly insects and their larvae, of which it consumes great quantities, the toad is a valuable friend to the farmer and gardener even though it also eats spiders and earthworms.

277

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Screech Owl Screech Owl Nature Bulletin No. 100 January 25, 1947 Forest Preserve District of Cook County William N. Erickson, President Roberts Mann, Superintendent of Conservation THE SCREECH OWL At the foot of a dead oak where we hoped to find some winter mushrooms beneath the grass and fallen leaves, we spied several pellets about the size and shape of the end of your thumb. They were clean and odorless, each containing the skull and bones of a mouse tightly wrapped in a layer of the animal's fur. Owls and hawks swallow their prey whole or in large pieces and later spit out the indigestible matter in the form of pellets. Up in this tree was a woodpecker hole from which the round unwinking yellow eyes of a screech owl glared at us. A screech owl, about the size of a robin but much chunkier, is our only small owl with ear tufts like "horns". They prey on mice, chipmunks and ground squirrels, fish, crayfish, amphibians, small snakes, angleworms, and large insects. When other food is scarce, and their fuzzy white young -- usually four in number -- require much food, they frequently kill birds but apparently not enough to seriously affect the bird population. No owl, of any species, should be killed.

278

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Eyeball Growth Eyeball Growth Name: Jade Hawk Status: N/A Age: N/A Location: N/A Country: N/A Date: N/A Question: Okay, I know I'm supposed to be able to answer questions here, but a friend who teaches grades 7 & 8 general science wants to know if the human eyeball is fully grown at birth. I checked my references, which are rather limited when it comes to human physiology, and found nothing. Can anyone help? Replies: The eye will still develop in size, pigmentation, and neurologically but I don't have the details here at hand. A kitten is born with eyes even more immature than human babies. Besides having sealed eyes that take about a week to open, they have retinas that a avascularized and need to undergo neovascularization to properly nourish and oxygenate the tissue. We have used the kitten to study retinopathy of prematurity, a condition caused in part by increased inspired oxygen. The kitten is also used in the study of diabetic retinopathy which a I think is the leading cause of blindness in the US. Look up publications by Dale Phelps, MD.

279

Two-Color Self-Seeding at LCLS | Stanford Synchrotron Radiation Lightsource

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Two-Color Self-Seeding at LCLS Two-Color Self-Seeding at LCLS Wednesday, September 18, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Franz-Josef Decker, Accelerator Directorate The Linac Coherent Light Source (LCLS) produces typically SASE FEL pulses with intensities of up to 5 mJ and at high photon energy an FEL bandwidth 0.2% (FWHM). Self-seeding with a diamond crystal reduces the bandwidth by a factor of 10 to 40. The range depends on which Bragg reflection is used, or the special setup of the electron beam like over-compression. The peak intensity level is lower by a factor of only five, giving the seeded beam an advantage of about 2.5 in average intensity over the use of a monochromator with SASE. At certain energies and crystal angles different Bragg lines cross which allows seeding at two or even three different colors inside the bandwidth

280

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Owls Owls Nature Bulletin No. 267-A April 29, 1967 Forest Preserve District of Cook County Richard B. Ogilvie, President Roland F. Eisenbeis, Supt. of Conservation OWLS The owls, of all our native birds, are least understood. Most kinds remain hidden, motionless and silent during the day and hunt only at night or in the dim twilight of morning and evening. Only a few, like our common Short-eared Owl and those big owls of the far north -- the Snowy Owl, the Great Gray Owl and the Hawk Owl -- habitually hunt in daytime. Because an owl' s feathers are peculiarly soft and fluffy, it flies as silently as a passing shadow, swoops upon its prey unheard, and its Indian name was "hush-wing". Since ancient times there have been many superstitions and legends about these birds. They have been regarded as the companions of sorcerers, witches, ghosts, hobgoblins and Satan himself. Their weird nocturnal hootings, gobblings and screams were and are believed to predict death, illness or disaster. Even today, in our southern states, the plaintive quavering cry of the Little Screech Owl -- which they call the "Shivering" Owl -- will cause some people to get out of bed and turn over their left shoe; others to throw a nail or other iron object into the fire. To the Greeks and Romans, the owl was a symbol of wisdom and was the companion of their goddess of wisdom.

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

281

Kerr-Newman solution as a Dirac particle

For m^2 < a^2 + q^2, with m, a, and q respectively the source mass, angular momentum per unit mass, and electric charge, the Kerr--Newman (KN) solution of Einstein's equation reduces to a naked singularity of circular shape, enclosing a disk across which the metric components fail to be smooth. By considering the Hawking and Ellis extended interpretation of the KN spacetime, it is shown first that, similarly to the electron-positron system, this solution presents four inequivalent classical states. Next, it is shown that due to the topological structure of the extended KN spacetime it does admit states with half-integral angular momentum. This last property is corroborated by the fact that, under a rotation of the space coordinates, those inequivalent states transform into themselves only after a 4pi rotation. As a consequence, it becomes possible to naturally represent them in a Lorentz spinor basis. The state vector representing the whole KN solution is then constructed, and its evolution is shown to be governed by the Dirac equation. The KN solution can thus be consistently interpreted as a model for the electron-positron system, in which the concepts of mass, charge and spin become connected with the spacetime geometry. Some phenomenological consequences of the model are explored.

H. I. Arcos; J. G. Pereira

2004-01-19T23:59:59.000Z

282

Primordial black holes from temporally enhanced curvature perturbation

Scalar field with generalized kinetic interactions metamorphoses depending on its field value, ranging from cosmological constant to stiff matter. We show that such a scalar field can give rise to temporal enhancement of the curvature perturbation in the primordial Universe, leading to efficient production of primordial black holes while the enhancement persists. If the inflation energy scale is high, those mini-black holes evaporate by the Hawking radiation much before Big Bang nucleosynthesis and the effective reheating of the Universe is achieved by the black hole evaporation. Dominance of PBHs and the reheating by their evaporation modify the expansion history of the primordial Universe. This results in a characteristic feature of the spectrum of primordial tensor modes in the DECIGO frequency band, opening an interesting possibility of testing PBH reheating scenario by measuring the primordial tensor modes. If the inflation energy scale is low, the PBH mass can be much larger than the solar mass. In this case, PBH is an interesting candidate for seeds for supermassive black holes residing in present galaxies.

Teruaki Suyama; Yi-Peng Wu; Jun'ichi Yokoyama

2014-06-02T23:59:59.000Z

283

Photons into axion-like particles conversion in Active Galactic Nuclei

The idea that photons can convert into axion-like particles (ALPs) $\\gamma \\to a$ in or around an AGN and reconvert back into photons $a \\to \\gamma$ in the Milky Way magnetic field has been put forward in 2008 and has recently attracted growing interest. Yet, so far nobody has estimated the conversion probability $\\gamma \\to a$ as carefully as allowed by present-day knowledge. Our aim is to fill this gap. We first remark that AGN that can be detected above 100 GeV are blazars, namely AGN with jets, with one of them pointing towards us. Moreover, blazars fall into two well defined classes: BL Lac objects (BL Lacs) and Flat Spectrum Radio Quasars (FSRQs), with drastically different properties. In this Letter we evaluate the $\\gamma \\to a$ conversion probability inside these two classes of blazars, taking also the host elliptical galaxy into account. Our findings are surprising. For, while in the case of BL Lacs the conversion probability turns out to be totally unpredictable due to the strong dependence on the values of the somewhat uncertain position of the emission region along the jet and strength of the magnetic field therein, for FSRQs we are able to make a clear-cut prediction. Our results are of paramount importance in view of the planned very-high-energy detectors like the CTA, HAWK and HISCORE, as well as for laboratory experiments like ALPS II at DESY and IAXO.

Fabrizio Tavecchio; Marco Roncadelli; Giorgio Galanti

2014-06-09T23:59:59.000Z

284

Conformal anomaly for 2D and 4D dilaton coupled spinors

Science Journals Connector (OSTI)

We study quantum dilaton coupled spinors in two and four dimensions. Making a classical transformation of the metric, the dilaton coupled spinor theory is transformed into the minimal spinor theory with another metric and in the 4D case a spinor also in the background of the nontrivial vector field. This makes it possible to calculate 2D and 4D dilaton-dependent conformal (or Weyl) anomalies easily. The anomaly-induced effective action for such spinors is derived. In the 2D case, the effective action reproduces, without any extra terms, the term added by hand in the quantum correction for the Russo-Susskind-Thorlacius model, which is exactly solvable. For the 4D spinor the chiral anomaly which depends explicitly on the dilaton is also found. As some applications we discuss supersymmetric black holes (BH’s) in dilatonic supergravity with Wess-Zumino-type matter and Hawking radiation in the same theory. As another application we investigate spherically reduced Einstein gravity with a 2D dilaton coupled fermion anomaly-induced effective action and show the existence of quantum-corrected Schwarzchild–de Sitter (Nariai) BH’s with multiple horizons.

Peter van Nieuwenhuizen; Shin’ichi Nojiri; Sergei D. Odintsov

1999-09-24T23:59:59.000Z

285

Quantum Geometry and Black Holes

We present an overall picture of the advances in the description of black hole physics from the perspective of loop quantum gravity. After an introduction that discusses the main conceptual issues we present some details about the classical and quantum geometry of isolated horizons and their quantum geometry and then use this scheme to give a natural definition of the entropy of black holes. The entropy computations can be neatly expressed in the form of combinatorial problems solvable with the help of methods based on number theory and the use of generating functions. The recovery of the Bekenstein-Hawking law and corrections to it is explained in some detail. After this, due attention is paid to the discussion of semiclassical issues. An important point in this respect is the proper interpretation of the horizon area as the energy that should appear in the statistical-mechanical treatment of the black hole model presented here. The chapter ends with a comparison between the microscopic and semiclassical app...

G., J Fernando Barbero

2015-01-01T23:59:59.000Z

286

Municipal sanitary landfills generate leachate that New York State regulations require to be collected and treated to avoid contaminating surface water and groundwater. One option for treating leachate is to haul it to municipal wastewater treatment facility. This option may be expensive, may require excessive energy for transportation, and may require pretreatment to protect the receiving facility`s processes. An alternative is on-site treatment and discharge. Personnel from the Town of Fenton, New York; Hawk Engineering, P.C.; Cornell University; and Ithaca College designed, built, and operated a pilot constructed wetland for treating leachate at the Town of Fenton`s municipal landfill. The system, consisting of two overland flow beds and two subsurface flow beds has been effective for 18 months in reducing levels of ammonia (averaging 85% removal by volatilization and denitrification) and total iron (averaging 95% removal by precipitation and sedimentation), two key constituents of the Fenton landfill`s leachate. The system effects these reductions with zero chemical and energy inputs and minimal maintenance. A third key constituent of the leachate, manganese, apparently passes through the beds with minimal removal. Details and wetland considerations are described.

Not Available

1993-11-01T23:59:59.000Z

287

Bulk emission of scalars by a rotating black hole

We study in detail the scalar-field Hawking radiation emitted into the bulk by a higher-dimensional, rotating black hole. We numerically compute the angular eigenvalues, and solve the radial equation of motion in order to find transmission factors. The latter are found to be enhanced by the angular momentum of the black hole, and to exhibit the well-known effect of superradiance. The corresponding power spectra for scalar fields show an enhancement with the number of dimensions, as in the non-rotating case. We compute the total mass loss rate of the black hole for a variety of black-hole angular momenta and bulk dimensions, and find that, in all cases, the bulk emission remains significantly smaller than the brane emission. The angular-momentum loss rate is also computed and found to have a smaller value in the bulk than on the brane. We present accurate bulk-to-brane emission ratios for a range of scenarios.

M. Casals; S. R. Dolan; P. Kanti; E. Winstanley

2008-07-17T23:59:59.000Z

288

(Abridged) The HST Frontier Fields project started at the end of 2013 with the aim of providing extremely deep images of 6 massive galaxy clusters. One of the main goals of this program is to push several telescopes to their limits in order to provide the best current view of the earliest stages of the Universe. We present a detailed analysis of $z$$\\sim$8 objects behind the HFFs lensing cluster, MACS0416-2403, combining 0.3-1.6 $\\mu$m imaging from HST, ground-based $K_s$ imaging from VLT HAWK-I, and 3.6 $\\mu$m and 4.5 $\\mu$m Spitzer Space Telescope. We apply the classical Lyman Break technique, combining non-detection criteria and color-selection. In order to avoid contamination by mid-$z$ interlopers, we require a strong break between optical and near infrared data. The luminosity function at $z$$\\sim$8 is computed using a MC method taking advantage of the SED-fitting results. A piece of cautionary information is gleaned from new deep optical photometry of a previously identified $z$$\\sim$8 galaxy in this c...

Laporte, N; Kim, S; Pelló, R; Bauer, F E; Bina, D; Brammer, G; De Leo, M A; Infante, L; Pérez-Fournon, I

2014-01-01T23:59:59.000Z

289

Excavations at the gravitationally collapsed site: Recent findings

Hawking effect was dug out of the gravitationally collapsed site forty years back when it was realised that quantum effects at the horizon could propagate outward to infinity giving rise to a thermal flux at late-times. However, the situation regarding non-asymptotic observers was never completely clear. Also, recently a debate has sprung in the community as to what would infalling observers perceive while crossing the horizon. We set out to settle this question and more at least semi-classically in the articles [arXiv:1304.2858] and [arXiv:1404.0684] with a fresh approach. We introduce a new set of coordinates that are regular everywhere, consider the adiabatic expansion of detector response and its link to the trajectory-dependent `effective' temperature/s and also local invariant observables, energy density and flux, built from renormalized stress energy tensor. This paper is a concise summary of the new procedure and the results obtained thereof.

Singh, Suprit

2014-01-01T23:59:59.000Z

290

Continuing our investigation of the regularization of the noise kernel in curved spacetimes [N. G. Phillips and B. L. Hu, Phys. Rev. D {\\bf 63}, 104001 (2001)] we adopt the modified point separation scheme for the class of optical spacetimes using the Gaussian approximation for the Green functions a la Bekenstein-Parker-Page. In the first example we derive the regularized noise kernel for a thermal field in flat space. It is useful for black hole nucleation considerations. In the second example of an optical Schwarzschild spacetime we obtain a finite expression for the noise kernel at the horizon and recover the hot flat space result at infinity. Knowledge of the noise kernel is essential for studying issues related to black hole horizon fluctuations and Hawking radiation backreaction. We show that the Gaussian approximated Green function which works surprisingly well for the stress tensor at the Schwarzschild horizon produces significant error in the noise kernel there. We identify the failure as occurring at the fourth covariant derivative order.

Nicholas G Phillips; B. L. Hu

2002-09-17T23:59:59.000Z

291

In Paper II [N. G. Phillips and B. L. Hu, previous abstract] we presented the details for the regularization of the noise kernel of a quantum scalar field in optical spacetimes by the modified point separation scheme, and a Gaussian approximation for the Green function. We worked out the regularized noise kernel for two examples: hot flat space and optical Schwarzschild metric. In this paper we consider noise kernels for a scalar field in the Schwarzschild black hole. Much of the work in the point separation approach is to determine how the divergent piece conformally transforms. For the Schwarzschild metric we find that the fluctuations of the stress tensor of the Hawking flux in the far field region checks with the analytic results given by Campos and Hu earlier [A. Campos and B. L. Hu, Phys. Rev. D {\\bf 58} (1998) 125021; Int. J. Theor. Phys. {\\bf 38} (1999) 1253]. We also verify Page's result [D. N. Page, Phys. Rev. {\\bf D25}, 1499 (1982)] for the stress tensor, which, though used often, still lacks a rigorous proof, as in his original work the direct use of the conformal transformation was circumvented. However, as in the optical case, we show that the Gaussian approximation applied to the Green function produces significant error in the noise kernel on the Schwarzschild horizon. As before we identify the failure as occurring at the fourth covariant derivative order.

Nicholas G Phillips; B. L. Hu

2002-09-17T23:59:59.000Z

292

Quantum fields in curved spacetime

We review the theory of quantum fields propagating in an arbitrary, classical, globally hyperbolic spacetime. Our review emphasizes the conceptual issues arising in the formulation of the theory and presents known results in a mathematically precise way. Particular attention is paid to the distributional nature of quantum fields, to their local and covariant character, and to microlocal spectrum conditions satisfied by physically reasonable states. We review the Unruh and Hawking effects for free fields, as well as the behavior of free fields in deSitter spacetime and FLRW spacetimes with an exponential phase of expansion. We review how nonlinear observables of a free field, such as the stress-energy tensor, are defined, as well as time-ordered-products. The "renormalization ambiguities" involved in the definition of time-ordered products are fully characterized. Interacting fields are then perturbatively constructed. Our main focus is on the theory of a scalar field, but a brief discussion of gauge fields is included. We conclude with a brief discussion of a possible approach towards a nonperturbative formulation of quantum field theory in curved spacetime and some remarks on the formulation of quantum gravity.

Stefan Hollands; Robert M. Wald

2014-06-10T23:59:59.000Z

293

Entanglement entropy of black holes

The entanglement entropy is a fundamental quantity which characterizes the correlations between sub-systems in a larger quantum-mechanical system. For two sub-systems separated by a surface the entanglement entropy is proportional to the area of the surface and depends on the UV cutoff which regulates the short-distance correlations. The geometrical nature of the entanglement entropy calculation is particularly intriguing when applied to black holes when the entangling surface is the black hole horizon. I review a variety of aspects of this calculation: the useful mathematical tools such as the geometry of spaces with conical singularities and the heat kernel method, the UV divergences in the entropy and their renormalization, the logarithmic terms in the entanglement entropy in 4 and 6 dimensions and their relation to the conformal anomalies. The focus in the review is on the systematic use of the conical singularity method. The relations to other known approaches such as 't Hooft's brick wall model and the Euclidean path integral in the optical metric are discussed in detail. The puzzling behavior of the entanglement entropy due to fields which non-minimally couple to gravity is emphasized. The holographic description of the entanglement entropy of the black hole horizon is illustrated on the two- and four-dimensional examples. Finally, I examine the possibility to interpret the Bekenstein-Hawking entropy entirely as the entanglement entropy.

Sergey N. Solodukhin

2011-04-19T23:59:59.000Z

294

Black hole entanglement entropy regularized in a freely falling frame

Science Journals Connector (OSTI)

We compute the black hole horizon entanglement entropy SE for a massless scalar field, first with a hard cutoff and then with high frequency dispersion, both imposed in a frame that falls freely across the horizon. Using WKB methods, we find that SE is finite for a hard cutoff or superluminal dispersion, because the mode oscillations do not diverge at the horizon and the contribution of high transverse momenta is cut off by the angular momentum barrier. For subluminal dispersion, the entropy depends on the behavior at arbitrarily high transverse momenta. In all cases it scales with the horizon area. For the hard cutoff it is linear in the cutoff, rather than quadratic. This discrepancy from the familiar result arises from the difference between the free-fall frame and the static frame in which a cutoff is usually imposed. In the superluminal case the entropy scales with a fractional power of the cutoff that depends on the index of the dispersion relation. Implications for the possible relation between regularized entanglement entropy and the Bekenstein-Hawking entropy are discussed. An appendix provides an explicit derivation of the entangled, thermal nature of the near-horizon free-fall vacuum for a dispersive scalar field in four dimensions.

Ted Jacobson and Renaud Parentani

2007-07-13T23:59:59.000Z

295

Suppression of Star Formation in the central 200 kpc of a z = 1.4 Galaxy Cluster

We present the results of an extended narrow-band H{\\alpha} study of the massive galaxy cluster XMMU J2235.3-2557 at z = 1.39. This paper represents a follow up study to our previous investigation of star-formation in the cluster centre, extending our analysis out to a projected cluster radius of 1.5 Mpc. Using the Near InfraRed Imager and Spectrograph (NIRI) on Gemini North we obtained deep H narrow-band imaging corresponding to the rest-frame wavelength of H{\\alpha} at the cluster's redshift. We identify a total of 163 potential cluster members in both pointings, excluding stars based on their near-IR colours derived from VLT/HAWK-I imaging. Of these 163 objects 14 are spectroscopically confirmed cluster members, and 20% are excess line-emitters. We find no evidence of star formation activity within a radius of 200 kpc of the brightest cluster galaxy in the cluster core. Dust-corrected star formation rates (SFR) of excess emitters outside this cluster quenching radius, RQ \\sim 200 kpc, are on average = 2.7...

Grutzbauch, Ruth; Jørgensen, Inger; Varela, Jesus

2012-01-01T23:59:59.000Z

296

Large-eddy simulations of impinging over-expanded supersonic jet noise for launcher applications

Science Journals Connector (OSTI)

During the lift-off phase of a space launcher powerful rocket motors generate harsh acoustic environment on the launch pad. Following the blast waves created at ignition jet noise is a major contributor to the acoustic loads received by the launcher and its payload. Recent simulations performed at ONERA to compute the noise emitted by solid rocket motors at lift-off conditions are described. Far-field noise prediction is achieved by associating a LES solution of the jet flow with an acoustics surface integral method. The computations are carried out with in-house codes CEDRE for the LES solution and KIM for Ffowcs Williams & Hawkings porous surface integration method. The test case is that of a gas generator fired vertically onto a 45 degrees inclined flat plate which impingement point is located 10 diameters from nozzle exit. Computations are run for varied numerical conditions such as turbulence modeling along the plate and different porous surfaces location and type. Results are discussed and compared with experimental acoustic measurements obtained by CNES at MARTEL facility.

2014-01-01T23:59:59.000Z

297

Acoustic white holes in flowing atomic Bose-Einstein condensates

We study acoustic white holes in a steadily flowing atomic Bose-Einstein condensate. A white hole configuration is obtained when the flow velocity goes from a super-sonic value in the upstream region to a sub-sonic one in the downstream region. The scattering of phonon wavepackets on a white hole horizon is numerically studied in terms of the Gross-Pitaevskii equation of mean-field theory: dynamical stability of the acoustic white hole is found, as well as a signature of a nonlinear back-action of the incident phonon wavepacket onto the horizon. The correlation pattern of density fluctuations is numerically studied by means of the truncated-Wigner method which includes quantum fluctuations. Signatures of the white hole radiation of correlated phonon pairs by the horizon are characterized; analogies and differences with Hawking radiation from acoustic black holes are discussed. In particular, a short wavelength feature is identified in the density correlation function, whose amplitude steadily grows in time since the formation of the horizon. The numerical observations are quantitatively interpreted by means of an analytical Bogoliubov theory of quantum fluctuations for a white hole configuration within the step-like horizon approximation.

Carlos Mayoral; Alessio Recati; Alessandro Fabbri; Renaud Parentani; Roberto Balbinot; Iacopo Carusotto

2010-09-30T23:59:59.000Z

298

Black Holes, Firewalls and Chaos from Gravitational Collapse

One of the most spectacular predictions of the general theory of relativity is the black hole, an object that plays a central role in modern physics [1,2,3] and astrophysics [4,5]. Black holes are, however, plagued by fundamental paradoxes that remain unresolved to this day. First, the black hole event horizon is teleological in nature [6], which means that we need to know the entire future space-time of the universe to determine the current location of the horizon. This is essentially impossible. Second, any information carried by infalling matter is lost once the material falls through the event horizon. Even though the black hole may later evaporate by emitting Hawking radiation [7], the lost information does not reappear, which has the rather serious and disturbing consequence that quantum unitarity is violated [8]. Here we propose that the above paradoxes are restricted to a particular idealized model of collapse first studied in the 1930s [9, 10] in which the event horizon, which defines the boundary of...

Joshi, Pankaj S

2014-01-01T23:59:59.000Z

299

This Remedial Investigation (RI) Report characterizes the nature and extent of contamination, evaluates the fate and transport of contaminants, and assesses risk to human health and the environment resulting from waste disposal and other US Department of Energy (DOE) operations in Bear Creek Valley (BCV). BCV, which is located within the DOE Oak Ridge Reservation (ORR) encompasses multiple waste units containing hazardous and radioactive wastes arising from operations at the adjacent Oak Ridge Y-12 Plant. The primary waste units discussed in this RI Report are the S-3 Site, Oil Landfarm (OLF), Boneyard/Burnyard (BYBY), Sanitary Landfill 1 (SL 1), and Bear Creek Burial Grounds (BCBG). These waste units, plus the contaminated media resulting from environmental transport of the wastes from these units, are the subject of this RI. This BCV RI Report represents the first major step in the decision-making process for the BCV watershed. The RI results, in concert with the follow-on FS will form the basis for the Proposed Plan and Record of Decision for all BCV sites. This comprehensive decision document process will meet the objectives of the watershed approach for BCV. Appendix G contains ecological risks for fish, benthic invertebrates, soil invertebrates, plants, small mammals, deer, and predator/scavengers (hawks and fox). This risk assessment identified significant ecological risks from chemicals in water, sediment, soil, and shallow ground water. Metals and PCBs are the primary contaminants of concern.

NONE

1996-09-01T23:59:59.000Z

300

Black Holes and the Third Law of Thermodynamics

We discuss in the framework of black hole thermodynamics some aspects relative to the third law in the case of black holes of the Kerr-Newman family. In the light of the standard proof of the equivalence between the unattainability of the zero temperature and the entropic version of the third law it is remarked that the unattainability has a special character in black hole thermodynamics. Also the zero temperature limit which obtained in the case of very massive black holes is discussed and it is shown that a violation of the entropic version in the charged case occurs. The violation of the Bekenstein-Hawking law in favour of zero entropy S_E=0 in the case of extremal black holes is suggested as a natural solution for a possible violation of the second law of thermodynamics. Thermostatic arguments in support of the unattainability are explored, and $S_E=0$ for extremal black holes is shown to be again a viable solution. The third law of black hole dynamics by W.Israel is then interpreted as a further strong corroboration to the picture of a discontinuity between extremal states and non-extremal ones.

F. Belgiorno; M. Martellini

2002-10-08T23:59:59.000Z

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to obtain the most current and comprehensive results.

301

Challenging the generalized second law

The generalized second law (GSL) of black hole thermodynamics states that the sum of changes in black hole entropy and the ordinary entropy of matter and fields outside the hole must be non-negative. In the classical limit, the GSL reduces to Hawking's area theorem. Neither law identifies the specific effects that make it work in particular situations. Motivated by Davies' recent gedanken experiment he used to infer a bound on the size of the fine structure constant from the GSL, we study a series of variants in which an electric test charge is lowered to a finite radius and then dropped into a Schwarzschild, a near-extremal magnetic Reissner-Nordstroem or a near-extremal Kerr black hole. For a classical charge, we demonstrate that a specific 'backreaction' effect is responsible for protecting the area theorem in the near-extremal examples. For the magnetically charged Reissner-Nordstroem hole an area theorem violation is defused by taking into account a subtle source of repulsion of the charge: the spinning up of the black hole in the process of bringing the charge down to its dropping point. In Kerr hole case, the electric self-force on the charge is sufficient to right matters. However, in all experiments involving an elementary charge, the full GSL would apparently be violated were the fine structure constant greater than about order unity. We argue that in this case a quantum effect, the Unruh-Wald quantum buoyancy, may protect the GSL.

Eling, Christopher; Bekenstein, Jacob D. [Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904 (Israel)

2009-01-15T23:59:59.000Z

302

Reversible and irreversible spacetime thermodynamics for general Brans-Dicke theories

We derive the equations of motion for Palatini F(R) gravity by applying an entropy balance law TdS={delta}Q+{delta}N to the local Rindler wedge that can be constructed at each point of spacetime. Unlike previous results for metric F(R), there is no bulk viscosity term in the irreversible flux {delta}N. Both theories are equivalent to particular cases of Brans-Dicke scalar-tensor gravity. We show that the thermodynamical approach can be used ab initio also for this class of gravitational theories and it is able to provide both the metric and scalar equations of motion. In this case, the presence of an additional scalar degree of freedom and the requirement for it to be dynamical naturally imply a separate contribution from the scalar field to the heat flux {delta}Q. Therefore, the gravitational flux previously associated to a bulk viscosity term in metric F(R) turns out to be actually part of the reversible thermodynamics. Hence we conjecture that only the shear viscosity associated with Hartle-Hawking dissipation should be associated with irreversible thermodynamics.

Chirco, Goffredo; Eling, Christopher; Liberati, Stefano [SISSA, Via Bonomea 265, 34136 Trieste (Italy); INFN Sezione di Trieste, Via Valerio 2, 34127 Trieste (Italy)

2011-01-15T23:59:59.000Z

303

Particle absorption by black holes and the generalized second law of thermodynamics

The change in entropy, /DeltaS, associated with the quasi-static absorption of a particle of energy u by a Schwarzschild black hole (ScBH) is approximately (u/T)-s, where T is the Hawking temperature of the black hole and s is the entropy of the particle. Motivated by the statistical interpretation of entropy, it is proposed here that absorption should be suppressed, but not forbidden, when /DeltaSabsorption cross-section to be sensitive to /DeltaS. A purely thermodynamic formulation of the probability for absorption is obtained from the standard relationship between microstates and entropy. If /DeltaS>>1 and s<__
__

Scott Funkhouser

2008-07-11T23:59:59.000Z

304

Thermal derivation of the Coleman-De Luccia tunneling prescription

We derive the rate for transitions between de Sitter vacua by treating the field theory on the static patch as a thermal system. This reproduces the Coleman-De Luccia formalism for calculating the rate, but leads to a modified interpretation of the bounce solution and a different prediction for the evolution of the system after tunneling. The bounce is seen to correspond to a sequence of configurations interpolating between initial and final configurations on either side of the tunneling barrier, all of which are restricted to the static patch. The final configuration, which gives the initial data on the static patch for evolution after tunneling, is obtained from one-half of a slice through the center of the bounce, while the other half gives the configuration before tunneling. The formalism makes no statement about the fields beyond the horizon. This approach resolves several puzzling aspects and interpretational issues concerning the Coleman-De Luccia and Hawking-Moss bounces. We work in the limit where the backreaction of matter on metric can be ignored, but argue that the qualitative aspects remain in the more general case. The extension to tunneling between anti-de Sitter vacua is discussed.

Brown, Adam R. [Physics Department, Columbia University, New York, New York 10027 (United States); Weinberg, Erick J. [Physics Department, Columbia University, New York, New York 10027 (United States); School of Physics, Korea Institute for Advanced Study, 207-43, Cheongnyangni2-dong, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of)

2007-09-15T23:59:59.000Z

305

Equivalence between Euclidean and in-in formalisms in de Sitter QFT

We study the relation between two sets of correlators in interacting quantum field theory on de Sitter space. The first are correlators computed using in-in perturbation theory in the expanding cosmological patch of de Sitter space (also known as the conformal patch, or the Poincare patch), and for which the free propagators are taken to be those of the free Euclidean vacuum. The second are correlators obtained by analytic continuation from Euclidean de Sitter; i.e., they are correlators in the fully interacting Hartle-Hawking state. We give an analytic argument that these correlators coincide for interacting massive scalar fields with any m{sup 2}>0. We also verify this result via direct calculation in simple examples. The correspondence holds diagram by diagram, and at any finite value of an appropriate Pauli-Villars regulator mass M. Along the way, we note interesting connections between various prescriptions for perturbation theory in general static spacetimes with bifurcate Killing horizons.

Higuchi, Atsushi [Department of Mathematics, University of York Heslington, York, YO10 5DD (United Kingdom); Marolf, Donald; Morrison, Ian A. [Physics Department, UCSB, Santa Barbara, California 93106 (United States)

2011-04-15T23:59:59.000Z

306

Cosmological Landscape From Nothing: Some Like It Hot

We suggest a novel picture of the quantum Universe -- its creation is described by the {\\em density matrix} defined by the Euclidean path integral. This yields an ensemble of universes -- a cosmological landscape -- in a mixed state which is shown to be dynamically more preferable than the pure quantum state of the Hartle-Hawking type. The latter is dynamically suppressed by the infinitely large positive action of its instanton, generated by the conformal anomaly of quantum fields within the cosmological bootstrap (the self-consistent back reaction of hot matter). This bootstrap suggests a solution to the problem of boundedness of the on-shell cosmological action and eliminates the infrared catastrophe of small cosmological constant in Euclidean quantum gravity. The cosmological landscape turns out to be limited to a bounded range of the cosmological constant $\\Lambda_{\\rm min}\\leq \\Lambda \\leq \\Lambda_{\\rm max}$. The domain $\\Lambdalandscape. The dependence of the cosmological constant range on particle phenomenology suggests a possible dynamical selection mechanism for the landscape of string vacua.

A. O. Barvinsky; A. Yu. Kamenshchik

2006-09-13T23:59:59.000Z

307

Emergent gravitational dynamics in relativistic Bose--Einstein condensate

Analogue models of gravity have played a pivotal role in the past years by providing a test bench for many open issues in quantum field theory in curved spacetime such as the robustness of Hawking radiation and cosmological particle production. More recently, the same models have offered a valuable framework within which current ideas about the emergence of spacetime and its dynamics could be discussed via convenient toy models. In this context, we study here an analogue gravity system based on a relativistic Bose--Einstein condensate. We show that in a suitable limit this system provides not only an example of an emergent spacetime (with a massive and a massless relativistic fields propagating on it) but also that such spacetime is governed by an equation with geometric meaning that takes the familiar form of Nordstr{\\"o}m theory of gravitation. In this equation the gravitational field is sourced by the expectation value of the trace of the effective stress energy tensor of the quasiparticles while the Newton and cosmological constants are functions of the fundamental scales of the microscopic system. This is the first example of analogue gravity in which a Lorentz invariant, geometric theory of semiclassical gravity emerges from an underlying quantum theory of matter in flat spacetime.

Alessio Belenchia; Stefano Liberati; Arif Mohd

2014-10-22T23:59:59.000Z

308

Black holes at the IceCube neutrino telescope

Science Journals Connector (OSTI)

If the fundamental Planck scale is about a TeV and the cosmic neutrino flux is at the Waxman-Bahcall level, quantum black holes are created daily in the Antarctic ice cap. We reexamine the prospects for observing such black holes with the IceCube neutrino-detection experiment. To this end, we first revise the black hole production rate by incorporating the effects of inelasticty, i.e., the energy radiated in gravitational waves by the multipole moments of the incoming shock waves. After that we study in detail the process of Hawking evaporation accounting for the black hole’s large momentum in the lab system. We derive the energy spectrum of the Planckian cloud which is swept forward with a large, O(106), Lorentz factor. (It is noteworthy that the boosted thermal spectrum is also relevant for the study of near-extremal supersymmetric black holes, which could be copiously produced at the Large Hadron Collider.) In the semiclassical regime, we estimate the average energy of the boosted particles to be less than 20% the energy of the ? progenitor. Armed with such a constraint, we determine the discovery reach of IceCube by tagging on soft (relative to what one would expect from charged current standard model processes) muons escaping the electromagnetic shower bubble produced by the black hole’s light descendants. The statistically significant 5? excess extends up to a quantum gravity scale ?1.3??TeV.

Luis A. Anchordoqui; Matthew M. Glenz; Leonard Parker

2007-01-09T23:59:59.000Z

309

Quantum Creation of a Universe with varying speed of light: $?$-problem and Instantons

This article is dedicated to cosmologies with variable speed of light (VSL) - models, which one can consider as a particular case of models of a modified gravitation. In quantum cosmology the closed universe can spontaneously nucleate out of the state with no classical space and time. As known, in case of classical cosmology with varying speed of light $c(t)$ it is possible to solve the horizon problem, the flatness problem and the $\\Lambda$-problem if $c=sa^n$ with $s$=const and $n0$. Thus, the semiclassical tunneling nucleation probability in VSL quantum cosmology is very different from that in quantum cosmology with $c$=const. In particular, it can be strongly suppressed for large values of $\\Lambda$. In addition, we propose two instantons that describe the nucleation of closed universes in VSL models. These solutions are akin to the Hawking-Turok instanton in sense of O(4) invariance but, unlike to it, are both non-singular. Moreover, using those solutions we can obtain the probability of nucleation which is suppressed for large value of $\\Lambda$ too. We also discuss some unusual properties of models with $n>0$.

Artyom V. Yurov; Valerian A. Yurov

2008-12-27T23:59:59.000Z

310

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Bird Nest Predation Bird Nest Predation Name: Susan Location: N/A Country: N/A Date: N/A Question: On the 18th of April, a pair of Northern Cardinals selected a nest site near the top of a dense, 8 foot holly tree, a foundation planting that obscures about 1/4 of our open front porch. They located the nest under the overhang of the roof, facing our front door. By the 21st, a clutch of three eggs had been laid and Mrs. C began to sit on the nest. We succeeded at keeping a low profile, despite the near proximity to our main entrance. She was relaxed and seemingly unworried by our quiet comings and goings. Yesterday morning, all was well, but sometime around midday, after almost a week of incubation, all three eggs and, it appears, Mrs. C, vanished without a trace! There is no obvious disturbance or damage to the nest or the immediate area. The interior of the nest is pristine ~ no feathers, eggshell bits, membrane material. Cats are rarely a problem. In addition to the typical Blue Jays and Crows, we have a lot of squirrels, raccoons, opossums, skunks and even a pair of red-tail hawks on our wooded acre and the surrounds. Due to, I believe, some nearby housing construction, I have observed a opossum during the day several times this past week and have noticed a new arrival, a woodchuck. With temperatures in the 50's, I think it is too chilly for snakes to be active. What would be your best guess as to what happened? Any chance the pair will return to the same nest and try again?

311

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

B B a c k t o t h e F u t u r e 6 S u m m e r i n C y b e r s p a c e 8 H o w T h e y S p e n t t h e S u m m e r o f Ã• 9 9 1 0 E x p e r i m e n t e r s B e t O n N e w S o f t w a r e 1 3 Ta l k o f t h e L a b MiniBooNE 2 F E R M I L A B A U. S. D E P A R T M E N T O F E N E R G Y L A B O R A T O R Y F N E E R W M S I Volume 22 Friday, September 3, 1999 Number 17 f Photo by Reidar Hahn Since the last installment in our series on the fledgling MiniBooNE experiment, physicists have been busy hawking their research proposal to the Department of Energy and the National Science Foundation. Both agencies promptly committed funds, and one mysterious well-wisher in New York City even sent in a $40 check. With money nearly in hand, the MiniBooNE scientists and engineers set to work six months ago on the final design for their detector and began pulling together a bid package for its construction. Their goal was to have construction underway

312

Using a collision model to design safer wind turbine rotors for birds

A mathematical model for collisions between birds and propeller-type turbine rotors identifies the variables that can be manipulated to reduce the probability that birds will collide with the rotor. This study defines a safety index--the clearance power density--that allows rotors of different sizes and designs to be compared in terms of the amount of wind energy converted to electrical energy per bird collision. The collision model accounts for variations in wind speed during the year and shows that for model rotors with simple, one-dimensional blades, the safety index increases in proportion to rotor diameter, and variable speed rotors have higher safety indexes than constant speed rotors. The safety index can also be increased by enlarging the region near the center of the rotor hub where the blades move slowly enough for birds to avoid them. Painting the blades to make them more visible might have this effect. Model rotors with practical designs can have safety indexes an order of magnitude higher than those for model rotors typical of the constant speeds rotors in common use today. This finding suggests that redesigned rotors could have collision rates with birds perhaps an order of magnitude lower than today`s rotors, with no reduction in the production of wind power. The empirical data that exist for collisions between raptors, such as hawks and eagles, and rotors are consistent with the model: the numbers of raptor carcasses found beneath large variable speed rotors, relative to the numbers found under small constant speed rotors, are in the proportions predicted by the collision model rather than in proportion to the areas swept by the rotor blades. However, uncontrolled variables associated with these data prevent a stronger claim of support for the model.

Tucker, V.A. [Duke Univ., Durham, NC (United States). Dept. of Zoology

1996-11-01T23:59:59.000Z

313

Physics Beyond the Standard Model: Exotic Leptons and Black Holes at Future Colliders

The Standard Model of particle physics has been remarkably successful in describing present experimental results. However, it is assumed to be only a low-energy effective theory which will break down at higher energy scales, theoretically motivated to be around 1 TeV. There are a variety of proposed models of new physics beyond the Standard Model, most notably supersymmetric and extra dimension models. New charged and neutral heavy leptons are a feature of a number of theories of new physics, including the `intermediate scale' class of supersymmetric models. Using a time-of-flight technique to detect the charged leptons at the Large Hadron Collider, the discovery range (in the particular scenario studied in the first part of this thesis) is found to extend up to masses of 950 GeV. Extra dimension models, particularly those with large extra dimensions, allow the possible experimental production of black holes. The remainder of the thesis describes some theoretical results and computational tools necessary to model the production and decay of these miniature black holes at future particle colliders. The grey-body factors which describe the Hawking radiation emitted by higher-dimensional black holes are calculated numerically for the first time and then incorporated in a Monte Carlo black hole event generator; this can be used to model black hole production and decay at next-generation colliders. It is hoped that this generator will allow more detailed examination of black hole signatures and help to devise a method for extracting the number of extra dimensions present in nature.

Christopher M. Harris

2005-02-01T23:59:59.000Z

314

We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other 'fixed-background' approaches to holography) and in mainstream 'Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the viewpoint of QFT in curved spacetime -- in the framework of 't Hooft's 'brick wall' model -- with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein Gordon field in the Hartle-Hawking-Israel state on 1+2-Schwarzschild AdS (BTZ) has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the 'correspondence principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to black hole entropy. Working on the assumption that similar results will hold for bulk QFT other than the Klein Gordon field and for Schwarzschild AdS in other dimensions, and recalling the first author's proposed resolution to the Mukohyama-Israel puzzle based on his 'matter-gravity entanglement hypothesis', we argue that, in Maldacena AdS/CFT, the algebra of the boundary CFT is isomorphic only to a proper subalgebra of the bulk algebra, albeit (at non-zero temperature) the (GNS) Hilbert spaces of bulk and boundary theories are still the 'same' -- the total bulk state being pure, while the boundary state is mixed (thermal). We also argue from the finiteness of its boundary (and hence, on our assumptions, also bulk) entropy at finite temperature, that the Rehren dual of the Maldacena boundary CFT cannot itself be a QFT and must, instead, presumably be something like a string theory.

Bernard S. Kay; L. Ortiz

2014-05-22T23:59:59.000Z

315

Estimating Radiological Doses to Predators Foraging in a Low-Level Radioactive Waste Management Area

Since 1957, Los Alamos National Laboratory has operated Area G as its low-level, solid radioactive waste management and disposal area. Although the waste management area is developed, plants, small mammals, and avian and mammalian predators still occupy the less disturbed and revegetated portions of the land. For almost a decade, we have monitored the concentrations of selected radionuclides in soils, plants, and small mammals at Area G. The radionuclides tritium, plutonium-238, and plutonium-239 are regularly found at levels above regional background in all three media. Based on radionuclide concentrations in mice collected from 1994 to 1999, we calculated doses to higher trophic levels (owl, hawk, kestrel, and coyote) that forage on the waste management area. These predators play important functions in the regional ecosystems and are an important part of local Native American traditional tales that identify the uniqueness of their culture. The estimated doses are compared to Department of Energy's interim limit of 0.1 rad/day for the protection of terrestrial wildlife. We used exposure parameters that were derived from the literature for each receptor, including Environmental Protection Agency's exposure factors handbook. Estimated doses to predators ranged from 9E-06 to 2E-04 rad/day, assuming that they forage entirely on the waste management area. These doses are greater than those calculated for predators foraging exclusively in reference areas, but are still well below the interim dose limit. We believe that these calculated doses represent upper-bound estimates of exposure for local predators because the larger predators forage over areas that are much greater than the 63-acre waste management area. Based on these results, we concluded that predators foraging on this area do not face a hazard from radiological exposure under current site conditions.

L.Soholt; G.Gonzales; P.Fresquez; K.Bennett; E.Lopez

2003-03-01T23:59:59.000Z

316

Black Hole Evaporation in an Expanding Universe

We calculate the quantum radiation power of black holes which are asymptotic to the Einstein-de Sitter universe at spatial and null infinities. We consider two limiting mass accretion scenarios, no accretion and significant accretion. We find that the radiation power strongly depends on not only the asymptotic condition but also the mass accretion scenario. For the no accretion case, we consider the Einstein-Straus solution, where a black hole of constant mass resides in the dust Friedmann universe. We find negative cosmological correction besides the expected redshift factor. This is given in terms of the cubic root of ratio in size of the black hole to the cosmological horizon, so that it is currently of order $10^{-5} (M/10^{6}M_{\\odot})^{1/3} (t/14 {Gyr})^{-1/3}$ but could have been significant at the formation epoch of primordial black holes. Due to the cosmological effects, this black hole has not settled down to an equilibrium state. This cosmological correction may be interpreted in an analogy with the radiation from a moving mirror in a flat spacetime. For the significant accretion case, we consider the Sultana-Dyer solution, where a black hole tends to increase its mass in proportion to the cosmological scale factor. In this model, we find that the radiation power is apparently the same as the Hawking radiation from the Schwarzschild black hole of which mass is that of the growing mass at each moment. Hence, the energy loss rate decreases and tends to vanish as time proceeds. Consequently, the energy loss due to evaporation is insignificant compared to huge mass accretion onto the black hole. Based on this model, we propose a definition of quasi-equilibrium temperature for general conformal stationary black holes.

Hiromi Saida; Tomohiro Harada; Hideki Maeda

2007-05-28T23:59:59.000Z

317

Unified first law of black-hole dynamics and relativistic thermodynamics

A unified first law of black-hole dynamics and relativistic thermodynamics is derived in spherically symmetric general relativity. This equation expresses the gradient of the active gravitational energy E according to the Einstein equation, divided into energy-supply and work terms. Projecting the equation along the flow of thermodynamic matter and along the trapping horizon of a blackhole yield, respectively, first laws of relativistic thermodynamics and black-hole dynamics. In the black-hole case, this first law has the same form as the first law of black-hole statics, with static perturbations replaced by the derivative along the horizon. There is the expected term involving the area and surface gravity, where the dynamic surface gravity is defined as in the static case but using the Kodama vector and trapping horizon. This surface gravity vanishes for degenerate trapping horizons and satisfies certain expected inequalities involving the area and energy. In the thermodynamic case, the quasi-local first law has the same form, apart from a relativistic factor, as the classical first law of thermodynamics, involving heat supply and hydrodynamic work, but with E replacing the internal energy. Expanding E in the Newtonian limit shows that it incorporates the Newtonian mass, kinetic energy, gravitational potential energy and thermal energy. There is also a weak type of unified zeroth law: a Gibbs-like definition of thermal equilibrium requires constancy of an effective temperature, generalising the Tolman condition and the particular case of Hawking radiation, while gravithermal equilibrium further requires constancy of surface gravity. Finally, it is suggested that the energy operator of spherically symmetric quantum gravity is determined by the Kodama vector, which encodes a dynamic time related to E.

Sean A. Hayward

1997-10-20T23:59:59.000Z

318

Comparing quantum black holes and naked singularities

There are models of gravitational collapse in classical general relativity which admit the formation of naked singularities as well as black holes. These include fluid models as well as models with scalar fields as matter. Even if fluid models were to be regarded as unphysical in their matter content, the remaining class of models (based on scalar fields) generically admit the formation of visible regions of finite but arbitrarily high curvature. Hence it is of interest to ask, from the point of view of astrophysics, as to what a stellar collapse leading to a naked singularity (or to a visible region of very high curvature) will look like, to a far away observer. The emission of energy during such a process may be divided into three phases - (i) the classical phase, during which matter and gravity can both be treated according to the laws of classical physics, (ii) the semiclassical phase, when gravity is treated classically but matter behaves as a quantum field, and (iii) the quantum gravitational phase. In this review, we first give a summary of the status of naked singularities in classical relativity, and then report some recent results comparing the semiclassical phase of black holes with the semiclassical phase of spherical collapse leading to a naked singularity. In particular, we ask how the quantum particle creation during the collapse leading to a naked singularity compares with the Hawking radiation from a star collapsing to form a black hole. It turns out that there is a fundamental difference between the two cases. A spherical naked star emits only about one Planck energy during its semiclassical phase, and the further evolution can only be determined by the laws of quantum gravity. This contrasts with the semiclassical evaporation of a black hole.

T. P. Singh

2000-12-21T23:59:59.000Z

319

From Color Glass Condensate to Quark Gluon Plasma through the event horizon

We propose a new thermalization scenario for heavy ion collisions which at sufficiently high energies implies the phase transition to the quark--gluon plasma. The key ingredient of our approach is the Hawking--Unruh effect: an observer moving with an acceleration $a$ experiences the influence of a thermal bath with an effective temperature $T = a / 2\\pi$, similar to the one present in the vicinity of a black hole horizon. For electric charges moving in external electromagnetic fields of realistic strength, the resulting temperature appears too small to be detected. However for partons in strong color fields the effect should be observable: in the Color Glass Condensate picture, the strength of the color-electric field is $E \\sim Q_s^2/g$ ($Q_s$ is the saturation scale, and $g$ is the strong coupling), the typical acceleration is $a \\sim Q_s$, and the heat bath temperature is $T = Q_s / 2\\pi \\sim 200$ MeV. In nuclear collisions at sufficiently high energies the effect can induce a rapid thermalization over the time period of $\\tau \\simeq 2\\pi/Q_s \\simeq 1\\ {\\rm fm}$ accompanied by phase transitions. We consider a specific example of chiral symmetry restoration induced by a rapid deceleration of the colliding nuclei. We argue that parton saturation in the initial nuclear wave functions is a necessary pre--condition for the formation of quark--gluon plasma. We discuss the implications of our "black hole thermalization" scenario for various observables in relativistic heavy ion collisions.

Dmitri Kharzeev; Kirill Tuchin

2005-01-25T23:59:59.000Z

320

CANDELS MULTI-WAVELENGTH CATALOGS: SOURCE DETECTION AND PHOTOMETRY IN THE GOODS-SOUTH FIELD

We present a UV to mid-infrared multi-wavelength catalog in the CANDELS/GOODS-S field, combining the newly obtained CANDELS HST/WFC3 F105W, F125W, and F160W data with existing public data. The catalog is based on source detection in the WFC3 F160W band. The F160W mosaic includes the data from CANDELS deep and wide observations as well as previous ERS and HUDF09 programs. The mosaic reaches a 5{sigma} limiting depth (within an aperture of radius 0.''17) of 27.4, 28.2, and 29.7 AB for CANDELS wide, deep, and HUDF regions, respectively. The catalog contains 34,930 sources with the representative 50% completeness reaching 25.9, 26.6, and 28.1 AB in the F160W band for the three regions. In addition to WFC3 bands, the catalog also includes data from UV (U band from both CTIO/MOSAIC and VLT/VIMOS), optical (HST/ACS F435W, F606W, F775W, F814W, and F850LP), and infrared (HST/WFC3 F098M, VLT/ISAAC Ks, VLT/HAWK-I Ks, and Spitzer/IRAC 3.6, 4.5, 5.8, 8.0 {mu}m) observations. The catalog is validated via stellar colors, comparison with other published catalogs, zero-point offsets determined from the best-fit templates of the spectral energy distribution of spectroscopically observed objects, and the accuracy of photometric redshifts. The catalog is able to detect unreddened star-forming (passive) galaxies with stellar mass of 10{sup 10} M{sub Sun} at a 50% completeness level to z {approx} 3.4 (2.8), 4.6 (3.2), and 7.0 (4.2) in the three regions. As an example of application, the catalog is used to select both star-forming and passive galaxies at z {approx} 2-4 via the Balmer break. It is also used to study the color-magnitude diagram of galaxies at 0 < z < 4.

Guo Yicheng; Barro, Guillermo; Faber, Sandra M.; Koo, David C. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA (United States); Ferguson, Henry C.; Dahlen, Tomas; Huang, Kuang-Han; Koekemoer, Anton M. [Space Telescope Science Institute, Baltimore, MD (United States); Giavalisco, Mauro [Department of Astronomy, University of Massachusetts, Amherst, MA (United States); Willner, S. P.; Ashby, Matthew L. N. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Donley, Jennifer L. [Los Alamos National Laboratory, Los Alamos, NM (United States); Fontana, Adriano; Galametz, Audrey; Grazian, Andrea [INAF-Osservatorio di Roma, I-00040 Monteporzio (Italy); Kocevski, Dale D. [Department of Physics and Astronomy, University of Kentucky, Lexington, KY (United States); McGrath, Elizabeth J. [Department of Physics and Astronomy, Colby College, Waterville, ME (United States); Peth, Michael [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD (United States); Salvato, Mara; Wuyts, Stijn, E-mail: ycguo@ucolick.org [Max-Planck-Institut fur Extraterrestrische Physik, D-85741 Garching bei Munchen (Germany); and others

2013-08-15T23:59:59.000Z

While these samples are representative of the content of NLE

they are not comprehensive nor are they the most current set.

We encourage you to perform a real-time search of NLE

to obtain the most current and comprehensive results.

321

This report presents a historical evaluation of the U12n Tunnel on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12n Tunnel was one of a series of tunnels used for underground nuclear weapons effects tests in Rainier and Aqueduct Mesas. A total of 22 nuclear tests were conducted in the U12n Tunnel from 1967 to 1992. These tests include Midi Mist, Hudson Seal, Diana Mist, Misty North, Husky Ace, Ming Blade, Hybla Fair, Mighty Epic, Diablo Hawk, Miners Iron, Huron Landing, Diamond Ace, Mini Jade, Tomme/Midnight Zephyr, Misty Rain, Mill Yard, Diamond Beech, Middle Note, Misty Echo, Mineral Quarry, Randsburg, and Hunters Trophy. DTRA sponsored all tests except Tomme and Randsburg which were sponsored by the Lawrence Livermore National Laboratory. Midnight Zephyr, sponsored by DTRA, was an add on experiment to the Tomme test. Eleven high explosive tests were also conducted in the tunnel and included a Stemming Plan Test, the Pre-Mill Yard test, the two seismic Non-Proliferation Experiment tests, and seven Dipole Hail tests. The U12n Tunnel complex is composed of the portal and mesa areas, encompassing a total area of approximately 600 acres (240 hectares). Major modifications to the landscape have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to testing, and construction of retention ponds. A total of 202 cultural features were recorded for the portal and mesa areas. At the portal area, features relate to the mining, construction, testing, and general everyday operational support activities within the tunnel. These include concrete foundations for buildings, ventilation equipment, air compressors, communications equipment, mining equipment, rail lines, retention ponds to impound tunnel effluent, and storage containers. Features on the mesa above the tunnel generally relate to tunnel ventilation and cooling, borehole drilling, and data recording facilities. Feature types include concrete foundations, instrument cable holes, drill holes, equipment pads, ventilation shafts, and ventilation equipment. The U12n Tunnel complex is eligible to the National Register of Historic Places under criteria a and c, consideration g of 36 CFR Part 60.4 as a historic landscape. Scientific research conducted at the tunnel has made significant contributions to the broad patterns of our history, particularly in regard to the Cold War era that was characterized by competing social, economic, and political ideologies between the former Soviet Union and the United States. The tunnel also possesses distinctive construction and engineering methods for conducting underground nuclear tests. The Desert Research Institute recommends that the U12n Tunnel area be left in place in its current condition and that the U12n Tunnel historic landscape be included in the NNSS monitoring program and monitored for disturbances or alterations on a regular basis.

Drollinger, Harold [DRI; Jones, Robert C [DRI; Bullard, Thomas F [DRI; Ashbaugh, Laurence J [DRI; Griffin, Wayne R

2011-06-01T23:59:59.000Z

322

A Historical Evaluation of the U12n Tunnel, Nevada National Security Site, Nye County, Nevada Part 1

This report presents a historical evaluation of the U12n Tunnel on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12n Tunnel was one of a series of tunnels used for underground nuclear weapons effects tests in Rainier and Aqueduct Mesas. A total of 22 nuclear tests were conducted in the U12n Tunnel from 1967 to 1992. These tests include Midi Mist, Hudson Seal, Diana Mist, Misty North, Husky Ace, Ming Blade, Hybla Fair, Mighty Epic, Diablo Hawk, Miners Iron, Huron Landing, Diamond Ace, Mini Jade, Tomme/Midnight Zephyr, Misty Rain, Mill Yard, Diamond Beech, Middle Note, Misty Echo, Mineral Quarry, Randsburg, and Hunters Trophy. DTRA sponsored all tests except Tomme and Randsburg which were sponsored by the Lawrence Livermore National Laboratory. Midnight Zephyr, sponsored by DTRA, was an add on experiment to the Tomme test. Eleven high explosive tests were also conducted in the tunnel and included a Stemming Plan Test, the Pre-Mill Yard test, the two seismic Non-Proliferation Experiment tests, and seven Dipole Hail tests. The U12n Tunnel complex is composed of the portal and mesa areas, encompassing a total area of approximately 600 acres (240 hectares). Major modifications to the landscape have resulted from four principal activities. These are road construction and maintenance, mining activities related to development of the tunnel complex, site preparation for activities related to testing, and construction of retention ponds. A total of 202 cultural features were recorded for the portal and mesa areas. At the portal area, features relate to the mining, construction, testing, and general everyday operational support activities within the tunnel. These include concrete foundations for buildings, ventilation equipment, air compressors, communications equipment, mining equipment, rail lines, retention ponds to impound tunnel effluent, and storage containers. Features on the mesa above the tunnel generally relate to tunnel ventilation and cooling, borehole drilling, and data recording facilities. Feature types include concrete foundations, instrument cable holes, drill holes, equipment pads, ventilation shafts, and ventilation equipment. The U12n Tunnel complex is eligible to the National Register of Historic Places under criteria a and c, consideration g of 36 CFR Part 60.4 as a historic landscape. Scientific research conducted at the tunnel has made significant contributions to the broad patterns of our history, particularly in regard to the Cold War era that was characterized by competing social, economic, and political ideologies between the former Soviet Union and the United States. The tunnel also possesses distinctive construction and engineering methods for conducting underground nuclear tests. The Desert Research Institute recommends that the U12n Tunnel area be left in place in its current condition and that the U12n Tunnel historic landscape be included in the NNSS monitoring program and monitored for disturbances or alterations on a regular basis.

Drollinger, Harold [DRI; Jones, Robert C [DRI; Bullard, Thomas F [DRI; Ashbaugh, Laurence J [DRI; Griffin, Wayne R [DRI

2011-06-01T23:59:59.000Z

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