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arXiv · 2204.08217

Static and spherically symmetric general relativity solutions in Minimal Theory of Bigravity

Masato Minamitsuji·Antonio De Felice·Shinji Mukohyama·Michele Oliosi
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Abstract

We investigate static and spherically symmetric solutions in the Minimal Theory of Bigravity (MTBG). First, we show that a pair of Schwarzschild-de Sitter spacetimes with different cosmological constants and black hole masses written in the spatially-flat Gullstrand-Painlev\'e (GP) coordinates is a solution in the self-accelerating branch of MTBG, while it cannot be a solution in the normal branch. We then illustrate how Schwarzschild-de Sitter solutions can become compatible with the normal branch when using different coordinates. We also confirm that the self-accelerating branch of MTBG admits static and spherically symmetric general relativity solutions with matter written in the spatially-flat coordinates, including neutron stars with arbitrary matter equations of state. Finally, we show that in the self-accelerating branch nontrivial solutions are given by the Schwarzschild-de Sitter metrics written in nonstandard coordinates.

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Masato Minamitsuji, Antonio De Felice, Shinji Mukohyama, Michele Oliosi. 2022-04-18. Static and spherically symmetric general relativity solutions in Minimal Theory of Bigravity. https://doi.org/10.1103/physrevd.105.123026

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