Universality and Criticality in Mass-less Scalar Field Collapse

TL;DR

This paper investigates the collapse of a mass-less scalar field, revealing a universal critical behavior that determines black hole formation or dispersion, characterized by a single parameter and a locally naked null singularity.

Contribution

It demonstrates that scalar field collapse outcomes depend on mode strengths and identifies a universal, ansatz-independent critical behavior with a zero-mass singularity.

Findings

Existence of a critical locally naked null singularity.

Collapse outcome depends on the ratio of collapsing to dispersing modes.

Geometrical mass of singularities approaches zero.

Abstract

In this paper, we observe the collapse of a mass-less scalar field covariantly. We show that the strengths of the collapsing and dispersing modes of this scalar field will decide whether the collapse will end up in a black-hole or disperse. We find a locally naked null singularity as a critical case between these two and confirm that there is a single dimensionless parameter that determine the end state. This work is ansatz-independent, hence, true for all mass-less scalar field families. We also show that the geometrical mass of these singularities go to zero.