Classical and quantum conformal gravity

Title: Classical and quantum conformal gravity

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Abstract

Conformal gravity, based on the action quadratic in the Weyl conformal curvature, constitutes a scale-invariant, classically-confining, asymptotically-free theory of gravitation. This theory is examined with a view toward assessing its viability as an alternative to Einstein gravity at the fundamental level. First, by extending the manifestly-covariant, six-dimensional formalism of Dirac, it is shown that conformal gravity arises uniquely as the local gauge theory of the conformal group SU(2,2). The exact, spherically-symmetric, electrovac solutions of the classical theory are obtained. Next, it is argued that the phenomenologically-required breakdown of conformal invariance is a consequence of divergent quantum fluctuations and the resulting energy-momentum tensor trace anomaly. A non-local effective gravitational action reproducing this anomaly is constructed. Finally, the effect of asymptotic freedom and the consequential local confinement of energy-momentum is analyzed.

Authors:: Riegert, R J

Publication Date:: 1986-01-01

Research Org.:: California Univ., San Diego (USA)

OSTI Identifier:: 6844972

Resource Type:: Thesis/Dissertation

Resource Relation:: Other Information: Thesis (Ph. D.)

Country of Publication:: United States

Language:: English

Subject:: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GRAVITATION; CONFORMAL GROUPS; QUANTUM GRAVITY; ANALYTICAL SOLUTION; CONFORMAL INVARIANCE; ENERGY-MOMENTUM TENSOR; FLUCTUATIONS; SYMMETRY BREAKING; FIELD THEORIES; INVARIANCE PRINCIPLES; LIE GROUPS; QUANTUM FIELD THEORY; SYMMETRY GROUPS; TENSORS; VARIATIONS; 645400* - High Energy Physics- Field Theory; 657003 - Theoretical & Mathematical Physics- Relativity & Gravitation

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                    Riegert, R J. Classical and quantum conformal gravity.  United States: N. p., 1986. 
        Web.

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                    Riegert, R J. Classical and quantum conformal gravity.  United States.

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                    Riegert, R J. Wed .  
        "Classical and quantum conformal gravity".  United States.

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@article{osti_6844972,

  title        = {Classical and quantum conformal gravity},

  author       = {Riegert, R J},

  abstractNote = {Conformal gravity, based on the action quadratic in the Weyl conformal curvature, constitutes a scale-invariant, classically-confining, asymptotically-free theory of gravitation. This theory is examined with a view toward assessing its viability as an alternative to Einstein gravity at the fundamental level. First, by extending the manifestly-covariant, six-dimensional formalism of Dirac, it is shown that conformal gravity arises uniquely as the local gauge theory of the conformal group SU(2,2). The exact, spherically-symmetric, electrovac solutions of the classical theory are obtained. Next, it is argued that the phenomenologically-required breakdown of conformal invariance is a consequence of divergent quantum fluctuations and the resulting energy-momentum tensor trace anomaly. A non-local effective gravitational action reproducing this anomaly is constructed. Finally, the effect of asymptotic freedom and the consequential local confinement of energy-momentum is analyzed.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/6844972},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1986},

  month        = {1}

}

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