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Back Reaction and Semiclassical Approximation of cosmological models coupled to matter

H. Wissowski·H. A. Kastrup
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Abstract

Bianchi -I, -III, and FRW type models minimally coupled to a massive spatially homogeneous scalar field (i.e. a particle) are studied in the framework of semiclassical quantum gravity. In a first step we discuss the solutions of the corresponding equation for a Schrödinger particle propagating on a classical background. The back reaction of the Schrödinger particle on the classical metric is calculated by means of the Wigner function and by means of the expectation value of the energy-momentum-tensor of the field as a source. Both methods in general lead to different results.

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H. Wissowski, H. A. Kastrup. 1997-03-04. Back Reaction and Semiclassical Approximation of cosmological models coupled to matter. https://doi.org/10.1016/s0920-5632(97)00394-0

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