Does Quantum Cosmology Predict a Constant Dilatonic Field?
Abstract
Quantum cosmology may permit to determine the initial conditions of the Universe. In particular, it may select a specific model between many possible classical models. In this work, we study a quantum cosmological model based on the string effective action coupled to matter. The Schutz's formalism is employed in the description of the fluid. A radiation fluid is considered. In this way, a time coordinate may be identified and the WheelerDeWitt equation reduces in the minisuperspace to a Schrödingerlike equation. It is shown that, under some quite natural assumptions, the expectation values indicate a null axionic field and a constant dilatonic field. At the same time the scale factor exhibits a bounce revealing a singularityfree cosmological model. In some cases, the mininum value of the scale factor can be related to the value of gravitational coupling.
 Publication:

International Journal of Modern Physics D
 Pub Date:
 2005
 DOI:
 10.1142/S0218271805005955
 arXiv:
 arXiv:grqc/0404034
 Bibcode:
 2005IJMPD..14..291A
 Keywords:

 98.80.Hw;
 04.60.Gw;
 Covariant and sumoverhistories quantization;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Theory;
 Quantum Physics
 EPrint:
 Latex file, 14 pages