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arXiv · 1910.01651

On the stability of bimetric structure formation

Marcus Högås·Francesco Torsello·Edvard Mörtsell
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Abstract

Bimetric gravity can reproduce the accelerated expansion of the Universe, without a cosmological constant. However, the stability of these solutions to linear perturbations has been questioned, suggesting exponential growth of structure in this approximation. We present a simple model of structure formation, for which an analytical solution is derived. The solution is well-behaved, showing that there is no physical instability with respect to these perturbations. The model can yield a growth of structure exhibiting measurable differences from $Λ$CDM.

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Marcus Högås, Francesco Torsello, Edvard Mörtsell. 2020-04-29. On the stability of bimetric structure formation. https://doi.org/10.1088/1475-7516%2F2020%2F04%2F046

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