New results on the dynamics of critical collapse

TL;DR

This paper investigates the behavior of scalar fields during critical gravitational collapse, providing approximate solutions and analyzing the dynamics in different regions of spacetime.

Contribution

It offers new approximate analytic expressions for metric functions and matter fields, enhancing understanding of scalar field collapse near criticality.

Findings

Derived analytic expressions for metric functions in large-radius regions

Reduced equations of motion to flat-spacetime form near the center

Analyzed the boundary conditions' impact on collapse dynamics

Abstract

We study the dynamics of the critical collapse of a spherically symmetric scalar field. Approximate analytic expressions for the metric functions and matter field in the large-radius region are obtained. In the central region, owing to the boundary conditions, the equation of motion for the scalar field is reduced to the flat-spacetime form.