On the third law of black hole dynamics

Abstract

The third law of black hole dynamics states that the surface gravity (temperature) of black hole cannot be reduced to zero in finite sequence of physical interactions. We argue that the same is true when surface gravity is replaced by gravitational charge. We demonstrate that the prescribed window for infalling energy and radiation pinches off as extremality ($M^2 = a^2 + Q^2 $) is approached.

9 pages, LaTeX version, Accepted in Physics Letters A