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arXiv · 1508.05864

New massive bigravity cosmologies with double matter coupling

Macarena Lagos·Johannes Noller
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Abstract

We study a previously largely unexplored branch of homogeneous and isotropic background solutions in ghost-free massive bigravity with consistent double matter coupling. For a certain family of parameters we find `self-inflated' FLRW cosmologies, i.e. solutions with an accelerated early-time period during the radiation-dominated era. In addition, these solutions also display an accelerated late-time period closely mimicking GR with a cosmological constant. Interestingly, within this family, the particular case of $β_1=β_3=0$ gives bouncing cosmologies, where there is an infinite contracting past, a non-zero minimum value of the scale factor at the bounce, and an infinite expanding future.

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Macarena Lagos, Johannes Noller. 2016-01-13. New massive bigravity cosmologies with double matter coupling. https://doi.org/10.1088/1475-7516%2F2016%2F01%2F023

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