A Precis of Dark Matter for Mathematicians

Abstract

We contribute a minireview of Dark Matter (DM), especially at galactic halo scales, with a mathematician reader in mind, highlighting the logic and empirical statements which underpin each of our current beliefs and which inform experimental Dark Matter searches. We pay attention to the shape of the DM halo around galaxies, how a prolate halo is a natural explanation of orbits around the galaxy with the surprising constant velocity, and how torsion of stellar streams emerges as a possible observable that can test the shape of the halo.