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No abstract available

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Published in summary form only.; CODEN: PRPLC.

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Journal Article

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Physics Reports; ISSN 0370-1573; ; v. 103(1-4); p. 233

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[en] The main purpose of this article is to report the progress of the path integral approach to quantum cosmology. Since quantum cosmology is an interdisciplinary field involving inputs from quantum theory, general relativity and cosmology, we begin with a brief survey of classical geometrodynamics and classical cosmology as well as an outline of the problems faced by any quantum theory of gravity. It is against this background that the authors' approach described in sections 3-5 is to be viewed and assessed. The Feynman path integral formalism to the extent neccessary for following this approach is described first in section 2.for the quantum analogues of the classical models. The results are generalized and discussed in the framework of the superspace metric. The difficult problem of the back reaction of quantum conformal fluctuations on the space-time metric is tackled in a semiclassical fashion in section 5. In this approach the conformal part of the metric is treated classically while the conformal fluctuations are replaced by their expectation values. The resulting field equations are solved in a few simple cases and physically interpreted. This preliminary work holds promise for a more complete theory of the future. In the end a solution on the flatness problem of classical cosmology is suggested within the framework of conformal fluctuations. (orig./HSI)

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Source

With 67 refs.; CODEN: PRPLC.

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Journal Article

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Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 100(3); p. 151-200

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ANALYTICAL SOLUTION, CONFORMAL INVARIANCE, COSMOLOGY, DIFFUSION, EINSTEIN FIELD EQUATIONS, EXPECTATION VALUE, FEYNMAN PATH INTEGRAL, FLUCTUATIONS, GRAVITATIONAL FIELDS, METRICS, PROPAGATOR, QUANTUM GRAVITY, REVIEWS, RIEMANN SPACE, SCHROEDINGER EQUATION, SECOND QUANTIZATION, SEMICLASSICAL APPROXIMATION, SINGULARITY, SPACE-TIME, STEADY-STATE CONDITIONS, SUPERSYMMETRY, UNIVERSE, WAVE PACKETS

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AbstractAbstract

[en] The derivation of gap equations and Ginzburg-Landau free energies for relativistic fermion systems is reviewed. The cases of superfluid neutron matter, superconducting electrons and superconducting and colour superconducting quark matter are described in detail. (orig.)

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Source

With 38 refs.; CODEN: PRPLC.

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Journal Article

Journal

Physics Reports; ISSN 0370-1573; ; v. 107(6); p. 325-385

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AbstractAbstract

[en] The theory and phenomenology of baryon echange processes are critically reviewed. As regards theory the main topics are the parity doublet problem and the patterns of exchange degenerate baryon trajectories implied by duality. In the phenomenological part, all baryon exchange reactions are considered, with the emphasis being on seeing how far simple dieas of pole exchange with the constraints implied by duality and broken SU(3) can be taken in forming an understanding of the data. (orig.)

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Secondary Subject

Source

With 372 refs.; CODEN: PRPLC.

Record Type

Journal Article

Literature Type

Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 103(6); p. 319-393

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ANNIHILATION, BARYON RESONANCES, BARYON-BARYON INTERACTIONS, BARYONS, CAPTURE, DEUTERONS, DIFFERENTIAL CROSS SECTIONS, DUALITY, ELASTIC SCATTERING, HADRON-HADRON INTERACTIONS, INCLUSIVE INTERACTIONS, MESON-BARYON INTERACTIONS, PAIR PRODUCTION, PHOTOPRODUCTION, POLARIZATION-ASYMMETRY RATIO, REGGE POLES, REGGE TRAJECTORIES, REVIEWS, SCATTERING AMPLITUDES, SPIN ORIENTATION, SU-3 GROUPS, SYMMETRY BREAKING, TENSOR MESONS, VECTOR MESONS

AMPLITUDES, BASIC INTERACTIONS, BOSONS, CHARGED PARTICLES, CROSS SECTIONS, DOCUMENT TYPES, ELECTROMAGNETIC INTERACTIONS, ELEMENTARY PARTICLES, FERMIONS, HADRONS, INTERACTIONS, LIE GROUPS, MESON RESONANCES, MESONS, ORIENTATION, PARTICLE INTERACTIONS, PARTICLE PRODUCTION, RESONANCE PARTICLES, SCATTERING, SU GROUPS, SYMMETRY GROUPS

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AbstractAbstract

[en] An overall view of the physics of QCD in the perturbative domain is presented in a form that could be of use both as an introduction to the subject with its main lines of current development and as a reference review text for the more expert readers as well. (orig.)

Primary Subject

Source

With 434 refs.

Record Type

Journal Article

Literature Type

Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 81(1); p. 1-129

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ANNIHILATION, DECAY AMPLITUDES, DEEP INELASTIC SCATTERING, DRELL MODEL, ELECTROMAGNETIC FORM FACTORS, ELECTRON-POSITRON INTERACTIONS, HADRONS, INCLUSIVE INTERACTIONS, JET MODEL, LAGRANGIAN FIELD THEORY, PARTICLE PRODUCTION, PARTONS, PERTURBATION THEORY, QUANTUM CHROMODYNAMICS, REVIEWS, STRUCTURE FUNCTIONS, TOTAL CROSS SECTIONS, UNIFIED GAUGE MODELS, WEAK HADRONIC DECAY

AMPLITUDES, CROSS SECTIONS, DECAY, DOCUMENT TYPES, ELEMENTARY PARTICLES, FIELD THEORIES, FORM FACTORS, FUNCTIONS, INELASTIC SCATTERING, INTERACTIONS, LEPTON-BARYON INTERACTIONS, LEPTON-HADRON INTERACTIONS, LEPTON-LEPTON INTERACTIONS, LEPTON-NUCLEON INTERACTIONS, MATHEMATICAL MODELS, PARTICLE DECAY, PARTICLE INTERACTIONS, PARTICLE MODELS, PARTICLE PROPERTIES, POSTULATED PARTICLES, QUANTUM FIELD THEORY, SCATTERING, TRANSITION AMPLITUDES, WEAK PARTICLE DECAY

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AbstractAbstract

[en] Bound states of the heaviest known quark, the b-quark, provides us with a powerful laboratory for testing fundamental ideas in physics. Four

^{3}S_{1}banti b bound states are now known to exist. Their masses and leptonic widths provide crucial information on the dynamics of quark binding. A large body of information has been collected in the past eighteen months at CESR on the four Y's. The Y'' was first resolved, the Y''' was discovered and proved to lie above the open flavor threshold. Finally, the first b-flavored particle, the pseudoscalar B-meson, was discovered by detecting its semileptonic decay. A brief description is given of the two detectors operating at CESR, and of heavy quark bound state phenomenology. Experimental results are presented and discussed in terms of current theoretical ideas. (orig.)Primary Subject

Source

With 68 refs.

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Journal Article

Literature Type

Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 81(3); p. 239-291

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BASIC INTERACTIONS, BOSONS, DECAY, DOCUMENT TYPES, ELEMENTARY PARTICLES, ENERGY LEVELS, HADRONS, INTERACTIONS, LEPTON-LEPTON INTERACTIONS, MASS, MESON RESONANCES, MESONS, PARTICLE DECAY, PARTICLE INTERACTIONS, PARTICLE PROPERTIES, POSTULATED PARTICLES, RESONANCE PARTICLES, VECTOR MESONS, WEAK INTERACTIONS, WEAK PARTICLE DECAY

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Weinert, U.

Duesseldorf Univ. (Germany, F.R.). Inst. fuer Theoretische Physik

Duesseldorf Univ. (Germany, F.R.). Inst. fuer Theoretische Physik

AbstractAbstract

[en] The basic ideas of general formalism for the solution of the Boltzmann equation are sketched briefly, distinguishing between separate formalisms for strong and weak driving forces in the sense of thermodynamics. Then a detailed disucssion of the latter case is given in the form of a generalized moment method based upon the use of Burnett functions. After the representation of all operators involved in the Boltzmann equation for this special system of basis functions, applications are discussed with increasing order of complexity to a simple gas, to the theoretical description of drift-tube (swarm) experiments, and, finally, to a multi-component gaseous mixture, considering in particular the relation between the one- and the multi-temperature model. (orig.)

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Source

CODEN: PRPLC.; Habil. Schr.

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Journal Article

Literature Type

Thesis/Dissertation

Journal

Physics Reports; ISSN 0370-1573; ; v. 91(6); p. 297-399

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AbstractAbstract

[en] The author describes the quark-gluon plasma in the framework of thermodynamics and quantum chromodynamics. (HSI)

Primary Subject

Source

18. rencontre de Moriond; Les Arcs (France); Mar 1982; CODEN: PRPLC.

Record Type

Journal Article

Literature Type

Conference

Journal

Physics Reports; ISSN 0370-1573; ; v. 88(5); p. 331-347

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AbstractAbstract

[en] The article contains a systematic presentation of the covariant diagrammatic technique for the effective action in gauge theories. The Schwinger-DeWitt technique is generalized and converted into a tool for the calculation of any covariant loop graphs in the effective action. In particular, this technique is extended to nonminimal but causal operators of any order. All calculations are carried out in a universal manner using only the form of the commutator of covariant derivatives. We show that one can even tabulate the universal loop graphs and present a table of a certain class of such graphs. The article can also serve as a reference book on the divergences of one-loop graphs. In particular, we present a complete algorithm for divergences in the determinant of the fourth-order operator. The calculational methods are developed for the recently proposed unique effective action in gauge theories. The unique counterterms in Einstein's theory are computed, and the question of asymptotic freedom in this theory is reexamined. (orig.)

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Source

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Journal Article

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Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 119(1); p. 1-74

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AbstractAbstract

[en] Two topics of lattice theory are reviewed. They include string tension and β-function calculations by strong coupling Hamiltonian methods for SU(3) gauge fields in 3 + 1 dimensions, and a 1/N-expansion for discrete gauge and spin systems in all dimensions. The SU(3) calculations give solid evidence for the coexistence of quark confinement and asymptotic freedom in the renormalized continuum limit of the lattice theory. The crossover between weak and strong coupling behavior in the theory is seen to be a weak coupling but non-perturbative effect. Quantitative relationships between perturbative and non-perturbative renormalization schemes are obtained for the O(N) nonlinear sigma models in 1 + 1 dimensions as well as the gauge theory in 3 + 1 dimensions. Analysis of the strong coupling expansion of the β-function for gauge fields suggests that it has cuts in the complex 1/g

^{2}-plane. A toy model of such a cut structure which naturally explains the abruptness of the theory's crossover from weak to strong coupling is presented. The relation of these cuts to other approaches to gauge field dynamics is discussed briefly. The dynamics underlying first order phase transitions in a wide class of lattice gauge theories is exposed by considering a class of models-P(N) gauge theories - which are soluble in the N → infinite limit and have non-trivial phase diagrams. The first order character of the phase transitions in Potts spin systems for N > 4 in 1 + 1 dimensions is explained in simple terms which generalizes to P(N) gauge systems in higher dimensions. The phase diagram of Ising lattice gauge theory coupled to matter fields is obtained in a 1/N expansion. A one-plaquette model (1 time-0 space dimensions) with a first-order phase transition in the N → infinite limit is discussed. (orig.)Primary Subject

Record Type

Journal Article

Literature Type

Progress Report

Journal

Physics Reports; ISSN 0370-1573; ; v. 67(1); p. 67-102D

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