Dynamics of cosmic strings with higherdimensional windings
Abstract
We consider Fstrings with arbitrary configurations in the Minkowski directions of a higherdimensional spacetime, which also wrap and spin around S{sup 1} subcycles of constant radius in an arbitrary internal manifold, and determine the relation between the higherdimensional and the effective fourdimensional quantities that govern the string dynamics. We show that, for any such configuration, the motion of the windings in the compact space may render the string effectively tensionless from a fourdimensional perspective, so that it remains static with respect to the large dimensions. Such a critical configuration occurs when (locally) exactly half the square of the string length lies in the large dimensions and half lies in the compact space. The critical solution is then seen to arise as a special case, in which the wavelength of the windings is equal to their circumference. As examples, long straight strings and circular loops are considered in detail, and the solutions to the equations of motion that satisfy the tensionless condition are presented. These solutions are then generalized to planar loops and arbitrary threedimensional configurations. Under the process of dimensional reduction, in which higherdimensional motion is equivalent to an effective worldsheet current (giving rise to a conserved charge), this phenomenonmore »
 Authors:
 Research Center for the Early Universe, School of Science, University of Tokyo, 731 Hongo, Bunkyoku, Tokyo 1130033 (Japan)
 The Institute for Fundamental Study, “The Tah Poe Academia Institute', Naresuan University, Phitsanulok 65000 (Thailand)
 (Thailand)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22454558
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 06; Other Information: PUBLISHERID: JCAP06(2015)023; OAI: oai:repo.scoap3.org:10789; Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CHIRALITY; EQUATIONS OF MOTION; FOURDIMENSIONAL CALCULATIONS; MATHEMATICAL SOLUTIONS; MINKOWSKI SPACE; SPACETIME; SPIN; STRING MODELS; STRING THEORY; WAVELENGTHS
Citation Formats
Yamauchi, Daisuke, Lake, Matthew J., and Thailand Center of Excellence in Physics, Ministry of Education,Bangkok 10400. Dynamics of cosmic strings with higherdimensional windings. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/06/023.
Yamauchi, Daisuke, Lake, Matthew J., & Thailand Center of Excellence in Physics, Ministry of Education,Bangkok 10400. Dynamics of cosmic strings with higherdimensional windings. United States. doi:10.1088/14757516/2015/06/023.
Yamauchi, Daisuke, Lake, Matthew J., and Thailand Center of Excellence in Physics, Ministry of Education,Bangkok 10400. 2015.
"Dynamics of cosmic strings with higherdimensional windings". United States.
doi:10.1088/14757516/2015/06/023.
@article{osti_22454558,
title = {Dynamics of cosmic strings with higherdimensional windings},
author = {Yamauchi, Daisuke and Lake, Matthew J. and Thailand Center of Excellence in Physics, Ministry of Education,Bangkok 10400},
abstractNote = {We consider Fstrings with arbitrary configurations in the Minkowski directions of a higherdimensional spacetime, which also wrap and spin around S{sup 1} subcycles of constant radius in an arbitrary internal manifold, and determine the relation between the higherdimensional and the effective fourdimensional quantities that govern the string dynamics. We show that, for any such configuration, the motion of the windings in the compact space may render the string effectively tensionless from a fourdimensional perspective, so that it remains static with respect to the large dimensions. Such a critical configuration occurs when (locally) exactly half the square of the string length lies in the large dimensions and half lies in the compact space. The critical solution is then seen to arise as a special case, in which the wavelength of the windings is equal to their circumference. As examples, long straight strings and circular loops are considered in detail, and the solutions to the equations of motion that satisfy the tensionless condition are presented. These solutions are then generalized to planar loops and arbitrary threedimensional configurations. Under the process of dimensional reduction, in which higherdimensional motion is equivalent to an effective worldsheet current (giving rise to a conserved charge), this phenomenon may be seen as the analogue of the tensionless condition which arises for superconducting and chiralcurrent carrying cosmic strings.},
doi = {10.1088/14757516/2015/06/023},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2015,
place = {United States},
year = 2015,
month = 6
}

We consider Fstrings with arbitrary configurations in the Minkowski directions of a higherdimensional spacetime, which also wrap and spin around S{sup 1} subcycles of constant radius in an arbitrary internal manifold, and determine the relation between the higherdimensional and the effective fourdimensional quantities that govern the string dynamics. We show that, for any such configuration, the motion of the windings in the compact space may render the string effectively tensionless from a fourdimensional perspective, so that it remains static with respect to the large dimensions. Such a critical configuration occurs when (locally) exactly half the square of the string lengthmore »

Higher dimensional flat embeddings of black strings in
We obtain (3+1) and (3+2)dimensional global flat embeddings of 2+1 uncharged and charged black strings, respectively. In particular, the charged black string, which is the dual solution of the BanadosTeitelboimZanelli black holes, is shown to be embedded in the same global embedding Minkowski space structure as that of the 2+1 charged de Sitter black hole solution. 
Gravitational phenomenology in higherdimensional theories and strings
We investigate gravitational phenomenology in compactified higherdimensional theories, with particular emphasis on the consequences in string theory of tensorinduced spontaneous Lorentzsymmetry breaking. The role played by this mechanism in causing a gravitational version of the Higgs effect and in compactification is explored. The experimental viability of compactified theories with zero modes is considered by examining nonleading but observable gravitational effects. Additional constraints from the observed cosmological properties of the Universe are uncovered. Our investigations significantly constrain many theories involving extra dimensions in their perturbative regime. To resolve the phenomenological difficulties one must generate masses for the higherdimensional components of themore » 
Massive strings in higherdimensional inhomogeneous spacetime
An inhomogeneous cosmological model with massive strings as source term is developed in a KaluzaKlein type of spacetime where the usual space exhibits spherical symmetry and the extra dimension is taken in the form of a circle. When an arbitrary constant in the solution vanishes an inhomogeneous cosmological model for pure dust is obtained, which further reduces to some particular forms of well known homogeneous models under suitable adjustment of arbitrary constants. The dynamical behaviour of the model is studied and it is found that the extra space admits of dimensional reduction via the successive appearances of one minimum andmore » 
Phenomenological gravitational constraints on strings and higherdimensional theories
We investigate measurable gravitational and cosmological effects in four dimensions that can arise from the compactification of higherdimensional theories incorporating gravity. We identify the nature of effects due to massless scalar components of the compactified higherdimensional metric and due to modifications of cosmological dynamics. Current experimental data impose constraints on the viability of many higherdimensional theories, including KaluzaKlein, supergravity, and string theories. The phenomenological problems can be avoided if the components of the metric in the higher dimensions acquire an effective mass. We survey some possible mechanisms for mass generation.