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Creators/Authors contains: "Allen, T.J."
  1. Both the Green-Schwarz and Siegel strings are presented in canonical form. Both systems are shown to describe the same number of physical degrees of freedom. The apparent extra symmetries of the Seigel string are not true symmetries but are combinations of second-class constraints. A formal quantization procedure is outlined and the problems of quantization are discussed.
  2. Dirac's procedure is applied to the Brink-Schwarz and Siegel superparticle systems. Both systems are exhibited to have the same first-class constraints. The difference between the systems is the lack of second-class fermionic constraints in the Siegel superparticle. Thus the Siegel superparticle has a phase space with twice as many fermionic degrees of freedom as the Brink-Schwarz superparticle.
  3. The end product of a decade of empirical study into communication behavior among technologists, this book gives a comprehensive view of the management of technical information. It attempts a unifying, systemic approach, unlike its predecessors in the field in which findings were not integrated into a more-complete presentation of the communication process in science or technology. Most important, the study shows how human and organizational systems can be restructured in order to bring about better person-to-person contact. Professor Allen offers models to describe organization and communication and to predict the relationships among the variables. Chapter 1 introduces a distinction betweenmore » the scientist and the technologist, whose differences in orientation have profound implications. Chapter 2 describes the research on which the book is based. Chapter 3 is an overview of the communication system in technology. Chapter 4 discusses the acquisition of technological information by the research and development organization. After the discussion in Chapter 5 of the need to promote communication and how it can be met, Chapter 6 returns to the topic of information acquisition and expands on it. Chapters 7 to 9 talk about how an organization's structure, and even its architecture and office layout, affect information dissemination. Chapter 10 offers a conclusion.« less
  4. A new harmonic'' Becchi-Rouet-Stora-Tyutin method is presented for quantizing those dynamical systems having second-class constraints which split into holomorphic and antiholomorphic algebras. These theories include those whose phase spaces are coadjoint orbits of a compact semisimple Lie group. The method also applies to theories with holomorphic first-class constraints which have nonvanishing brackets with their antiholomorphic conjugates. An operatorial quantization, resembling supersymmetric quantum mechanics, is presented. In addition, a general path integral is given and is shown to reduce to that given by Batalin, Fradkin, and Vilkovisky.
  5. In this paper, the 4-dimensional theory of a 1-form Abelian gauge field A coupled to a 2-form (antisymmetric tensor) potential B. The two gauge invariances of the theory admit a coupling mB F where F is the field strength (F = dA) of A. It is shown that this theory is a unitary, renormalizable theory of a massive spin-one field with no additional degrees of freedom. In this sense, it is a generalization to four dimensions of topological mechanisms in two dimensions (the Schwinger model) and three dimensions (Chern-Simons theory). The issue of spontaneous symmetry breaking is also examined.
  6. We examine the quantization of the motion of two charged vortices in a Ginzburg-Landau theory for the fractional quantum Hall effect recently proposed by the first two authors. The system has two second-class constraints which can be implemented either in the reduced phase space or Dirac-Gupta-Bleuler formalism. Using the intrinsic formulation of statistics, we show that these two ways of implementing the constraints are inequivalent unless the vortices are quantized with conventional statistics, either fermionic or bosonic.
  7. The effect of postwounding local radiation was measured in an animal model. Tensile strength and histologic appearance of wounds irradiated on Day 0, 3, and 5 were studied. The irradiated wounds were all significantly weaker than the nonirradiated wounds, but delaying the radiation did not benefit wound healing.
  8. We consider systems with second-class constraints or, equivalently, first-class holomorphic constraints. We show that the harmonic Becchi-Rouet-Stora-Tyutin method of quantizing systems with bosonic holomorphic constraints extends to systems having both bosonic and fermionic holomorphic constraints. The ghosts for bosonic holomorphic constraints in the harmonic BRST method have a Poisson brackets structure different from that of the ghosts in the usual BRST method, which applies to systems with real first-class constraints. Apart from this exotic ghost structure for bosonic constraints, the new feature of the harmonic BRST method is the introduction of two new holomorphic BRST charges [Theta] and [bar [Theta]]more » and the addition of an extra term [minus][beta][l brace][Theta],[bar [Theta]][r brace] to the BRST-invariant Hamiltonian. We apply the Fradkin-Vilkovisky theorem to general systems with mixed bosonic and fermionic holomorphic constraints and show that, taking an appropriate limit, the extra term in the harmonic BRST-modified path integral reproduces the correct Senjanovic measure.« less
  9. Single crystals superconducting La/sub 2-//sub x/Sr/sub x/CuO/sub 4/ (xapprox.0.08)= have been investigated in the temperature range 15--298 K and are found to undergo a structural phase transition below room temperature, but above 180 K. Detailed analysis of the diffraction-peak profiles obtained below the transition temperature indicates a breakup of the macroscopic crystals into multiple domains of different orientations. Several cooling and warming cycles always reverse the samples into one-domain single crystals at room temperature. Complicated peak profiles prevent the determination of the exact symmetry and structure below the phase transition.
  10. Starting from Buchm{umlt u}ller{close_quote}s observation that a chromoelectric flux tube meson will exhibit only the Thomas-type spin-orbit interaction, we show that a model built upon the related assumption that a quark feels only a constant radial chromoelectric field in its rest frame implies a complete relativistic effective Hamiltonian that can be written explicitly in terms of quark canonical variables. The model yields linear Regge trajectories and exhibits some similarities to scalar confinement, but with the advantage of being more closely linked to QCD. {copyright} {ital 1997} {ital The American Physical Society}
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