Time Evolution of Entropy of a Charged Domain Wall during Gravitational Collapse

Abstract

We study the time evolution of the entropy of a collapsing charged spherical domain wall, from the point of view of an asymptotic observer, by investigating the entropy of the entire system (i.e. charged domain wall and radiation) and induced radiation alone during the collapse. By taking the difference, we find the entropy of the collapsing charged domain wall, since this is the object which will form a black hole. We find that for large values of time (times larger than $tf_-/R_+\approx8$), the entropy of the collapsing domain wall is a constant, which is of the same order as the Bekenstein-Hawking entropy.