# Dark stars: gravitational and electromagnetic observables

## TL;DR

This paper models rotating dark stars made of self-interacting dark matter, analyzing their properties, universal relations, and distinguishing features from black holes in gravitational wave observations.

## Contribution

It constructs equilibrium models of dark stars with fermionic and bosonic matter, demonstrating their universal relations and non-compactness compared to black holes.

## Key findings

- Dark stars obey I-Love-Q relations similar to neutron stars.
- Dark stars are less compact than black holes, allowing potential observational distinction.
- Models include both fermionic and bosonic dark matter equations of state.

## Abstract

Theoretical models of self-interacting dark matter represent a promising answer to a series of open problems within the so-called collisionless cold dark matter (CCDM) paradigm. In case of asymmetric dark matter, self-interactions might facilitate gravitational collapse and potentially lead to formation of compact objects predominantly made of dark matter. Considering both fermionic and bosonic equations of state, we construct the equilibrium structure of rotating dark stars, focusing on their bulk properties, and comparing them with baryonic neutron stars. We also show that these dark objects admit the $I$-Love-$Q$ universal relations, which link their moments of inertia, tidal deformabilities, and quadrupole moments. Finally, we prove that stars built with a dark matter equation of state are not compact enough to mimic black holes in general relativity, thus making them distinguishable in potential events of gravitational interferometers.