Ultralight bosons for strong gravity applications from simple Standard Model extensions

TL;DR

This paper proposes simple Standard Model extensions that produce ultralight bosons, leading to new astrophysical objects like bosonic stars and non-Kerr black holes across a wide mass range, with potential observable implications.

Contribution

It introduces specific Standard Model extensions that generate ultralight bosons with astrophysical relevance, detailing their properties and implications for compact objects.

Findings

Ultralight bosons can form new compact objects and black holes.

Models predict bosonic stars and non-Kerr black holes in astrophysical mass ranges.

Potential observable effects in astrophysics and gravitational wave signals.

Abstract

We construct families, and concrete examples, of simple extensions of the Standard Model that can yield ultralight {real or} complex vectors or scalars with potential astrophysical relevance. Specifically, the mass range for these putative fundamental bosons ($\sim 10^{-10}-10^{-20}$ eV) would lead dynamically to both new non-black hole compact objects (bosonic stars) and new non-Kerr black holes, with masses of $\sim M_\odot$ to $\sim 10^{10} M_\odot$, corresponding to the mass range of astrophysical black hole candidates (from stellar mass to supermassive). For each model, we study the properties of the mass spectrum and interactions after spontaneous symmetry breaking, discuss its theoretical viability and caveats, as well as some of its potential and most relevant phenomenological implications {linking them to the} physics of compact objects.