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Quantum Isotropization of the Universe

N. Pinto-Neto·A. F. Velasco·R. Colistete Jr
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Abstract

We consider minisuperspace models constituted of Bianchi I geometries with a free massless scalar field. The classical solutions are always singular (with the trivial exception of flat space-time), and always anisotropic once they begin anisotropic. When quantizing the system, we obtain the Wheeler-DeWitt equation as a four-dimensional massless Klein-Gordon equation. We show that there are plenty of quantum states whose corresponding bohmian trajectories may be non-singular and/or presenting large isotropic phases, even if they begin anisotropic, due to quantum gravitational effects. As a specific example, we exhibit field plots of bohmian trajectories for the case of gaussian superpositions of plane wave solutions of the Wheeler-DeWitt equation which have those properties. These conclusions are valid even in the absence of the scalar field.

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N. Pinto-Neto, A. F. Velasco, R. Colistete Jr. 2000-01-24. Quantum Isotropization of the Universe. https://doi.org/10.1016/s0375-9601(00)00706-4

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