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Numerical Bianchi I solutions in semi-classical gravitation

Sandro P. Vitenti·Daniel Müller
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Abstract

It is believed that soon after the Planck era, spacetime should have a semi-classical nature. In this context we consider quantum fields propagating in a classical gravitational field and study the backreaction of these fields, using the expected value of the energy-momentum tensor as source of the gravitational field. According to this theory, the escape from General Relativity theory is unavoidable. Two geometric counter-term are needed to regularize the divergences which come from the expected value. There is a parameter associated to each counter-term and in this work we found numerical solutions of this theory to particular initial conditions, for general Bianchi Type I spaces. We show that even though there are spurious solutions some of them can be considered physical. These physical solutions include de Sitter and Minkowski that are obtained asymptotically.

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Sandro P. Vitenti, Daniel Müller. 2006-08-15. Numerical Bianchi I solutions in semi-classical gravitation. https://doi.org/10.1103/physrevd.74.063508

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