Static Planck stars from effective loop quantum gravity

TL;DR

This paper derives effective loop quantum gravity equations for spherically symmetric spacetimes, revealing solutions like Planck-scale stars without horizons that could impact dark matter theories and black hole evolution.

Contribution

It introduces a new effective Tolman-Oppenheimer-Volkoff equation within loop quantum gravity, predicting Planck-scale, horizonless stellar objects as potential black hole remnants.

Findings

Existence of Planck-mass, horizonless solutions

Potential dark matter candidates among miniature stars

Agreement with loop quantum cosmology for homogeneous cases

Abstract

Effective loop quantum gravity dynamics are derived for spherically symmetric spacetimes with a perfect fluid matter content. For homogeneous spacetimes, the effective dynamics agree with the standard results of loop quantum cosmology, while the equations for static solutions give an effective Tolman-Oppenheimer-Volkoff equation. There exist solutions to the effective Tolman-Oppenheimer-Volkoff equation that have a mass of the order of the Planck mass, a Planckian radius, and no horizon; these miniature stars could potentially contribute to dark matter, and could be an end state for an evaporating black hole.