Rise and fall of conformal scalar-metric quantum gravity

Thesis/Dissertation · Sun Jan 01 00:00:00 EST 1984

OSTI ID:5371132

Tsamis, N C

A systematic study of a gravitational action possessing local conformal invariance is undertaken. The spontaneous breaking of the conformal symmetry induces general relativity as an effective long distance limit through the vacuum expectation value of an unphysical scalar field. The Ward identities of the broken theory guarantee the stability of Minkowski spacetime or, equivalently, the vanishing of the cosmological constant to all orders in any consistent perturbation expansion. This result persists when the theory is coupled to the standard U(1) SU(2) SU(3) model with its electroweak symmetry broken by radiative corrections. A particularly natural small parameter is the ratio of the gravitational degrees of freedom to the matter ones, 1/N. In this perturbation expansion the theory is asymptotically free and renormalizable in a simple way. The author shows that this expansion predicts the spontaneous breaking of local conformation symmetry. Furthermore, all ghost degrees of freedom acquire gauge fixing dependent masses strongly suggesting the unitarity of the theory. A simple prescription is exhibited establishing the classical as well as quantum equivalence between pure metric and conformal scalar-metric gravitational theories. As a result, any Weyl invariant theory is incapable of resolving the cosmological constant problem. Strong arguments indicate that no realistic quantum gravity theory can be constructed possessing local coordinate and conformal invariance.

• Research Organization: Harvard Univ., Boston, MA (USA)
• OSTI ID: 5371132
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
QUANTUM GRAVITY
CONFORMAL INVARIANCE
EQUIVALENCE PRINCIPLE
FUNDAMENTAL CONSTANTS
PERTURBATION THEORY
RENORMALIZATION
SCALAR FIELDS
STANDARD MODEL
SYMMETRY BREAKING
VACUUM STATES
WARD IDENTITY
FIELD THEORIES
INVARIANCE PRINCIPLES
MATHEMATICAL MODELS
PARTICLE MODELS
QUANTUM FIELD THEORY
UNIFIED GAUGE MODELS
645400* - High Energy Physics- Field Theory