Description 
1 online resource (xi, 139 pages) 
Series 
World Scientific lecture notes in physics ; v. 69 

World Scientific lecture notes in physics ; v. 69

Contents 
Ch. 1. Introduction  ch. 2. The gravitational field as a constrained Hamiltonian system. 2.1. Momentum and Hamiltonian constraints. 2.2. Minisuperspaces as constrained systems. 2.3. Quantization  ch. 3. Deparametrization and path integral quantization. 3.1. The identification of time. 3.2. Gaugeinvariant action for a parametrized system. 3.3. Path integral. 3.4. Examples  ch. 4. Homogeneous relativistic cosmologies. 4.1. Isotropic universes. 4.2. Anisotropic universes  ch. 5. String cosmologies. 5.1. String theory on background fields. 5.2. String cosmological models. 5.3. Path integral quantization  ch. 6. Canonical quantization. 6.1. Approximate solutions of the WheelerDeWitt equation. 6.2. Gauge fixation and Schrodinger equation for isotropic models. 6.3. The Taub universe. 6.4. String cosmologies  ch. 7. Discussion 
Summary 
The problem of time is a central feature of quantum cosmology: differing from ordinary quantum mechanics, in cosmology there is nothing "outside" the system which plays the role of clock, and this makes difficult the obtention of a consistent quantization. A possible solution is to assume that a subset of the variables describing the state of the universe can be a clock for the remaining of the system. Following this line, in this book a new proposal consisting in the previous identification of time by means of gauge fixation is applied to the quantization of homogeneous cosmological models. Both path integral and canonical formulations are studied for relativistic and string cosmologies; in particular, a complete chapter about low energy string cosmology is included. The required basic concepts (as for example the Hamiltonian formulation of General Relativity) are reviewed, so that the book can be of interest not only for a researcher but also for a student 
Bibliography 
Includes bibliographical references (pages 133135) and index 
Notes 
Print version record 
Subject 
Quantum gravity.


Space and time.


Path integrals.


Gauge invariance.


Hamiltonian systems.


SCIENCE  Cosmology.


Gauge invariance


Hamiltonian systems


Path integrals


Quantum gravity


Space and time


Física teórica.

Form 
Electronic book

ISBN 
9789812778376 

9812778373 
