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arXiv · 2012.06401

On stability of Friedmann-Lema\^itre-Robertson-Walker solutions in doubled geometries

Arkadiusz Bochniak·Andrzej Sitarz
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Abstract

Motivated by the models of geometry with discrete spaces as additional dimensions we investigate the stability of cosmological solutions in models with two metrics of the Friedmann-Lema\^itre-Robertson-Walker type. We propose an effective gravity action that couples the two metrics in a similar manner as in the bimetric theory of gravity and analyse whether standard solutions with identical metrics are stable under small perturbations.

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Arkadiusz Bochniak, Andrzej Sitarz. 2020-12-11. On stability of Friedmann-Lema\^itre-Robertson-Walker solutions in doubled geometries. https://doi.org/10.1103/physrevd.103.044041

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