Universal threshold for primordial black hole formation

Universal threshold for primordial black hole formation

This paper mathematically proves that there is a universal threshold for primordial black hole formation, expressed in terms of the volume-averaged compaction function. This threshold is independent of the shape of the initial density perturbation that collapses to form the black hole. The key insight is that at the threshold of black hole formation, the collapsing configuration displays persistent self-similarity near the center, a fundamental property of critical gravitational collapse.