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in subjects: "Quantum Gravity"

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Soft-group-manifold structure of supergravity, and the proof of unitarity

The Soft Group Manifold (SGM) method of gauging a non-internal group is reviewed. Applications to three different versions of Extended Supergravity are presented. Then the geometric identification of the ghost fields and BRS equations, another aspect of the Group Manifold method, is summarized. The results are applied to Supergravity, and a completion of the proof of Unitarity of Sterman, Townsend, and Van Nieuwenhuizen is provided. 3 figures.

Date: January 1, 1979

Creator: Thierry-Mieg, J. & Ne'eman, Y.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Theoretical particle physics. Progress report, December 1, 1079-November 30, 1980. [Physics Dept. , Indiana Univ]

Work during the past year ranged from phenomenological studies of various quark systems to applications of quantum chromodynamics and lattice gauge theories. On the phenomenological side for mesons, studies of the charmonium and bottomonium families as well as the spectrum of states containing a single b-quark continued. As a result of some improved measurements, the topic of baryon magnetic moments was reconsidered. At the same time the properties of highly excited 3-quark systems were conside… more

Date: August 1, 1980

Creator: Hendry, A.W.; Lichtenberg, D.B. & Weingarten, D.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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GUTs, SUSY GUTs and SUPER GUTs

We review the motivations for extending grand unified theories with particular emphasis on supersymmetry and its phenomenological and cosmological fallout, and comment on the relevance of quantum gravity. 67 references.

Date: July 1, 1982

Creator: Gaillard, M. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Problems in unification and supergravity

Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented. (WHK)

Date: January 1, 1984

Creator: Farrar, G. & Henyey, F. (eds.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cosmology in theories with extra dimensions

Some possible cosmological effects of the existence of extra compact dimensions are discussed. Particular attention is given to the possibility that extra dimensions might naturally lead to an inflationary Universe scenario.

Date: January 1, 1985

Creator: Kolb, E.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Gravitational properties of antimatter

Quantum gravity is at the forefront of modern particle physics, yet there are no direct tests, for antimatter, of even the principle of equivalence. We note that modern descriptions of gravity, such as fibre bundles and higher dimensional spacetimes, allow violations of the commonly stated form of the principle of equivalence, and of CPT. We review both indirect arguments and experimental tests of the expected gravitational properties of CPT-conjugate states. We conclude that a direct experimen… more

Date: January 1, 1985

Creator: Goldman, T. & Nieto, M.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Classical geometrical interpretation of ghost fields and anomalies in Yang-Mills theory and quantum gravity

The reinterpretation of the BRS equations of Quantum Field Theory as the Maurer Cartan equation of a classical principal fiber bundle leads to a simple gauge invariant classification of the anomalies in Yang Mills theory and gravity.

Date: May 14, 1985

Creator: Thierry-Mieg, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Testing the surrogate zeta-function method

Use of the surrogate zeta-function method was crucial in calculating the Casimir energy in non-Abelian Kaluza-Klein theories. We establish the validity of this method for the case that the background metric is (Euclidean space)x(N-sphere). Our techniques do not apply to the case where the background is (Minkowski-space)x(N-sphere).

Date: October 1, 1985

Creator: Chodos, A. & Myers, E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The gravitational properties of antimatter

It is argued that a determination of the gravitational acceleration of antimatter towards the earth is capable of imposing powerful constraints on modern quantum gravity theories. Theoretical reasons to expect non-Newtonian non-Einsteinian effects of gravitational strength and experimental suggestions of such effects are reviewed. 41 refs. (LEW)

Date: September 1, 1986

Creator: Goldman, T.; Hughes, R.J. & Nieto, M.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The inverse-square law and quantum gravity

This paper briefly discusses a modification to central potential of gravity when antimatter is involved and the possible existence of quantum gravity and a fifth force of nature. 1 ref. (LSP)

Date: January 1, 1988

Creator: Nieto, M.M.; Goldman, T. & Hughes, R.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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New gravitational forces from quantum theory

When a classical theory is quantized, new physical effects result. The prototypical example is the Lamb Shift of quantum electrodynamics. Even though this phenomenon could be parametrized by the ''Uehling Potential,'' it was always realized that it was a quantum aspect of electromagnetism, not a ''new force'' of nature. So, too, with theories of quantum gravity. Generically they predict that there will be spin-1 (graviphoton) and spin-0 (graviscalar) partners of the spin-2 graviton. At some lev… more

Date: January 1, 1988

Creator: Nieto, M.M.; Goldman, T. & Hughes, R.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quantum gravity and new forces

The quantum-gravity-inspired phenomenology for gravitational forces is described. New gravitational phenomena, qualitatively similar to those attributed to the so-called )openreverse arrowquotes)fifth-force)closereverse arrowquotes) are to be expected. The parameters of a model with these features have been constrained by the geophysical tests of the inverse-square law of Stacey, et al. This model is then able to explain the apparent discrepancies between the recent resuilts of Thieberger and o… more

Date: January 1, 1988

Creator: Hughes, R.J.; Goldman, T. & Nieto, M.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quantum measurements and the environment induced transition from quantum to classical

Interaction between a quantum system and its environment can be often regarded as a measurement, in the course of which one of the system observables influences the evolution of the external degrees of freedom and is thus ''monitored'' by the environment. The resulting loss of quantum coherence erases part of the density matrix responsible for the correlations between the eigenstates of the monitored observable. This mechanism is very efficient even in the limit of weak coupling. Indeed, the cl… more

Date: January 1, 1988

Creator: Zurek, W.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Wormholes and cosmology

We review Coleman's wormhole mechanism for the vanishing of the cosmological constant. We find a discouraging result that wormholes much bigger than the Planck size are generated. We also consider the implications of the wormhole theory for cosmology. 7 refs., 2 figs.

Date: October 1, 1988

Creator: Klebanov, I. & Susskind, L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Physics with ultra-low energy antiprotons

The experimental observation that all forms of matter experience the same gravitational acceleration is embodied in the weak equivalence principle of gravitational physics. However no experiment has tested this principle for particles of antimatter such as the antiproton or the antihydrogen atom. Clearly the question of whether antimatter is in compliance with weak equivalence is a fundamental experimental issue, which can best be addressed at an ultra-low energy antiproton facility. This paper… more

Date: January 1, 1989

Creator: Holtkamp, D. B.; Holzscheiter, M. H. & Hughes, R. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Theoretical nuclear physics---elementary particles

This report briefly discusses the following topics: Thermodynamics with Wilson Fermions; beta function with Wilson Fermions; grand challenge; light flavors and nonperturbative QCD; the spin structure of the proton; the heavy Higgs Meson Problem; the heavy top quark problem; SU(2) Higgs Model; nontrivial quantum electrodynamics; vortex sheet dynamics; random surfaces and quantum gravity; strange baryon matter; supersymmetric model with the Higgs as a lepton; and Hamilton equations on group manif… more

Date: January 1, 1989

Creator: Kuti, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Quantum mechanical stabilization of Minkowski signature wormholes

When one attempts to construct classical wormholes in Minkowski signature Lorentzian spacetimes violations of both the weak energy hypothesis and averaged weak energy hypothesis are encountered. Since the weak energy hypothesis is experimentally known to be violated quantum mechanically, this suggests that a quantum mechanical analysis of Minkowski signature wormholes is in order. In this note I perform a minisuperspace analysis of a simple class of Minkowski signature wormholes. By solving the… more

Date: May 19, 1989

Creator: Visser, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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2 + 1 dimensional quantum gravity and the braid group

This paper discusses the following on quantum gravity: 2 + 1 gravity as a Chern-Simons theory; quantization; dynamics; the Braid group; and the emergence of space and time. 16 refs., 3 figs. (LSP)

Date: October 1, 1989

Creator: Carlip, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Geometric continuum regularization of quantum field theory

An overview of the continuum regularization program is given. The program is traced from its roots in stochastic quantization, with emphasis on the examples of regularized gauge theory, the regularized general nonlinear sigma model and regularized quantum gravity. In its coordinate-invariant form, the regularization is seen as entirely geometric: only the supermetric on field deformations is regularized, and the prescription provides universal nonperturbative invariant continuum regularization … more

Date: November 8, 1989

Creator: Halpern, M.B. (California Univ., Berkeley, CA (USA). Dept. of Physics)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Environment-induced superselection in cosmology

Interaction between a quantum system and its environment can be often regarded as a measurement, in the course of which one of the system observables influences the evolution of the external degrees of freedom and is thus monitored'' by the environment. This causes the system to decohere.'' Loss of quantum coherence erases part of the density matrix responsible for the correlations between the eigenstates of the monitored observables. This mechanism is very efficient even in the limit of weak c… more

Date: January 1, 1990

Creator: Zurek, W.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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(Problems in particle theory)

This report discusses gauge theories, quantum gravity, Ginsburg-Landau theory of superconductivity, cosmic strings, and High-{Tc} superconductivity. (LSP)

Date: January 1, 1990

Creator: Sage, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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(Theory of weak interactions and related topics; and study of e sup + e sup minus interactions)

This report contains brief discussions on the following topics: Higher point anomalous amplitudes; topological phase of quantum gravity; chiral symmetry breaking at finite temperature; Skyrmions as representations of current algebras; D {ge} 4 critical phenomena: self-duality, infinite dimensional symmetries and hypercomplex analyticity; D {ge} 3 topological field theories: anionic membranes and division algebras, geometric quantization by the method of orbits; and novel non-perturbative approa… more

Date: January 1, 1990

Creator: Chang, Lay Nam & Tze, C.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Progress report for a research program in theoretical high energy physics

Research this past year was carried out in the fields of cosmic strings and galaxy formation, inflationary models of the universe, topological defects and phase transitions, group contractions and chiral fermions, low-frequency approximations in (QCD), loop bremsstrahlung of e{sup +}e{sup {minus}} and {mu}{sup +}{mu}{sup {minus}} pairs in heavy-ion collisions, approximations to solutions of non-linear differential equations, the use of continued functions'' as solution to vortex problems, strin… more

Date: June 30, 1990

Creator: Feldman, D.; Fried, H.M.; Jevicki, A.; Kang, Kyungsik & Tan, Chung-I.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A quenched c = 1 critical matrix model

We study a variant of the Penner-Distler-Vafa model, proposed as a c = 1 quantum gravity: quenched' matrix model with logarithmic potential. The model is exactly soluble, and exhibits a two-cut branching as observed in multicritical unitary matrix models and multicut Hermitian matrix models. Using analytic continuation of the power in the conventional polynomial potential, we also show that both the Penner-Distler-Vafa model and our quenched' matrix model satisfy Virasoro algebra constraints.

Date: December 1, 1990

Creator: Qiu, Zongan & Rey, Soo-Jong.

Item Type: Report

Partner: UNT Libraries Government Documents Department