English

On the stability of bimetric structure formation

General Relativity and Quantum Cosmology 2020-04-30 v2 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

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\LambdaCDM.

Keywords

Cite

@article{arxiv.1910.01651,
  title  = {On the stability of bimetric structure formation},
  author = {Marcus Högås and Francesco Torsello and Edvard Mörtsell},
  journal= {arXiv preprint arXiv:1910.01651},
  year   = {2020}
}

Comments

15 pages, 7 figures. v2 slight updates in accordance with the published version

R2 v1 2026-06-23T11:34:04.835Z