Near- and sub-solar-mass naked singularities and black holes from transmutation of white dwarfs

TL;DR

This paper proposes that white dwarfs can transform into black holes or naked singularities by capturing primordial dark matter, providing a potential explanation for observed near-solar-mass black holes and offering a new way to study dark matter and compact objects.

Contribution

It introduces a mechanism for white dwarf transmutation into black holes or naked singularities via dark matter capture, a novel formation pathway for sub-solar-mass compact objects.

Findings

White dwarfs can transmute into black holes or naked singularities.

Dark matter capture can explain near-solar-mass black holes.

Transmutation events can be tested through merger rate observations.

Abstract

Recent gravitational wave events have suggested the existence of near-solar-mass black holes which cannot be formed via stellar evolution. This has opened up a tantalizing possibility of future detections of both black holes and naked singularities in this mass range. Existence of naked singularities is a topical and fundamental physics issue, but their formation mechanism is not yet clear. Here, we show that some white dwarfs can realistically transmute into black holes and naked singularities with a wide range of near- and sub-solar-mass values by capturing asymmetric or non-self-annihilating primordial dark matter (PDM) particles. We argue that, while a type Ia supernova due to the accumulation of dark matter at the core of a white dwarf could also be a possibility, the transmutation of a white dwarf into a black hole or a naked singularity is a viable consequence of the capture of non-self-annihilating PDM particles. These white dwarf transmutations can have a significant role in probing the physics of dark matter and compact objects, and could be tested using the rates and locations of mergers over the cosmological time scale.