Spin-2 dark matter from anisotropic Universe in bigravity [CL]

http://arxiv.org/abs/2211.15873


Bigravity is one of the natural extensions of general relativity and contains an additional massive spin-2 field which can be a good candidate for dark matter. To discuss the production of spin-2 dark matter, we study fixed point solutions of the background equations for axisymmetric Bianchi type-I Universes in two bigravity theories without Boulware-Deser ghost, i.e., Hassan-Rosen bigravity and Minimal Theory of Bigravity. We investigate the local and global stability of the fixed points and classify them. Based on the general analysis, we propose a new scenario where spin-2 dark matter is produced by the transition from an anisotropic fixed point solution to isotropic one. The produced spin-2 dark matter can account for all or a part of dark matter and can be directly detected by laser interferometers in the same way as gravitational waves.

Read this paper on arXiv…

Y. Manita, K. Aoki, T. Fujita, et. al.
Wed, 30 Nov 22
73/81

Comments: 15 pages, 3 figures