Topics in the semiclassical quantization of gravitation

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7019954

Ratra, B V

Three problems are discussed in which general coordinate covariance and quantum mechanics play fundamental roles. A functional approach to scalar quantum field theory in n + 1 dimensional de Sitter spacetime is formulated, and the functional Schroedinger equation is solved for the conformally and minimally coupled scalar fields in both the k = 0 and k = 1 gauges. It is shown that there is a natural initial condition, the requirement that the field energy remain finite as the scale factor a becomes small, which specifies a unique, time-dependent, de Sitter vacuum state. It is argued that spontaneously broken continuous symmetries are always dynamically restored in de Sitter spacetime. Second, the author discusses the canonical quantization of gravitation in the vielbein formalism and derives the Harrison-Zeldovich spectrum by perturbatively solving the Wheeler-DeWitt equations for an inflating universe coupled to a scalar field in 2 + 1 and 3 + 1 dimensions. Finally, he presents a gauge invariant action that describes the propagation of the superstring in curves superspace in the presence of background super Yang-Mills fields. It is shown that this action possesses the local fermionic world sheet symmetry needed for a consistent coupling of the string to background fields. Some other aspects of the superspace nonlinear sigma-model described by this action are also discussed.

• Research Organization: Stanford Univ., CA (USA)
• OSTI ID: 7019954
• Country of Publication: United States
• Language: English

Related Subjects

645400* -- High Energy Physics-- Field Theory
657002 -- Theoretical & Mathematical Physics-- Classical & Quantum Mechanics
657003 -- Theoretical & Mathematical Physics-- Relativity & Gravitation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
DE SITTER GROUP
DIFFERENTIAL EQUATIONS
EQUATIONS
FIELD THEORIES
GAUGE INVARIANCE
GRAVITATION
INVARIANCE PRINCIPLES
LIE GROUPS
MECHANICS
PARTIAL DIFFERENTIAL EQUATIONS
QUANTIZATION
QUANTUM FIELD THEORY
QUANTUM MECHANICS
SCALAR FIELDS
SCHROEDINGER EQUATION
SPACE-TIME
SYMMETRY GROUPS
WAVE EQUATIONS
YANG-MILLS THEORY