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Does Quantum Cosmology Predict a Constant Dilatonic Field?

F. G. Alvarenga·A. B. Batista·J. C. Fabris
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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 Wheeler-DeWitt equation reduces in the minisuperspace to a Schrödinger-like 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 singularity-free cosmological model. In some cases, the mininum value of the scale factor can be related to the value of gravitational coupling.

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F. G. Alvarenga, A. B. Batista, J. C. Fabris. 2004-04-07. Does Quantum Cosmology Predict a Constant Dilatonic Field?. https://doi.org/10.1142/s0218271805005955

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