http://arxiv.org/abs/2103.16954
We propose a new method to constrain alternative models for dark matter with observations. Specifically, we consider hybrid models in which cold dark matter (CDM) phenomena on cosmological scales and Modified Newtonian Dynamics (MOND) phenomena on galactic scales share a common origin. Various such models were recently proposed. They typically contain a mode that is directly coupled to matter (for MOND) and has a non-relativistic sound speed (for CDM). This allows even non-relativistic objects like stars to lose energy through Cherenkov radiation. This is unusual. Most modified gravity models have a relativistic sound speed, so that only high-energy cosmic rays emit Cherenkov radiation. We discuss the consequences of this Cherenkov radiation from stars.
T. Mistele
Thu, 1 Apr 2021
15/71
Comments: 10 pages, 2 figures. Essay written for the Gravity Research Foundation 2021 Awards for Essays on Gravitation
You must be logged in to post a comment.