Physics
Scientific paper
May 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000phrvd..61j4012a&link_type=abstract
Physical Review D (Particles, Fields, Gravitation, and Cosmology), Volume 61, Issue 10, 15 May 2000, id.104012
Physics
2
Lower Dimensional Models, Minisuperspace Models
Scientific paper
In this work we consider some aspects of classical and quantum cosmology in a model of two-dimensional dilaton gravity due to Callan, Giddings, Harvey, and Strominger. We describe matter by a perfect dust fluid. We start by reviewing perfect fluids in two spacetime dimensions following the standard treatment in general relativity. We obtain the equations of motion in the velocity-potential representation and give the action that would lead to them. We then consider the geometrodynamical formulation of the model and in particular obtain an expression for the Hamiltonian density of the dust matter. This turns out to be rather difficult to work with and a great simplification occurs when we restrict ourselves to the homogeneous case. Furthermore, taking the dust to be pressureless we solve the classical equations of motion for the scale factor and the dilaton field. We show that the Universe goes through cycles of expansion and contraction. We demonstrate the absence of particle horizons. Next we carry out the quantization of the model in minisuperspace and discuss its consequences for quantum cosmology. We solve the Wheeler-DeWitt equation in the WKB approximation and obtain the terms of order G-1 and G0 in the expansion in powers of the gravitational constant G. We show that depending on initial conditions one can obtain expanding or contracting solutions. The Universe can, starting from some initial state, expand to infinite size and then contract. The limitations of semiclassical analysis however prevent one from following the contraction right down to zero value for the scale factor.
No associations
LandOfFree
Classical and quantum cosmology in a model of two-dimensional dilaton gravity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Classical and quantum cosmology in a model of two-dimensional dilaton gravity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Classical and quantum cosmology in a model of two-dimensional dilaton gravity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1200142