What a difference a quadrupole makes?

TL;DR

This paper explores how deviations from spherical symmetry, specifically mass quadrupole moments, influence the behavior of static vacuum solutions and the resulting collision energies near exotic compact objects, differing from black hole scenarios.

Contribution

It analyzes the effects of mass quadrupole moments on static vacuum solutions and their impact on particle collision energies near exotic compact objects.

Findings

Quadrupole moments significantly alter collision energies near compact objects.

Collision processes differ markedly from those near black holes.

Non-spherical symmetry impacts the physics of black hole mimickers.

Abstract

We consider some implications of the departure from spherical symmetry for static solutions of the vacuum Einstein's equations describing black hole mimickers. In particular, we investigate how the presence of mass quadrupole moment affects the collision energy of test particles. We show that collision processes in the vicinity of such exotic compact sources with non vanishing mass quadrupole moment may be significantly different from those in the vicinity of black holes.