Speaker
Description
Recently it has been shown that the third law of black hole mechanics can be violated: an exactly extremal Reissner-Nordström black hole can form in finite time in the gravitational collapse of matter with a large charge to mass ratio. However, it has also been proved that this cannot happen if the matter satisfies a “supersymmetric” lower bound on its energy in terms of its charge. In this talk, I will discuss related results for gravity with a negative cosmological constant in both three and four spacetime dimensions.
In the four-dimensional case, a supersymmetric Kerr-Newman-AdS black hole cannot be formed in the gravitational collapse of matter satisfying the aforementioned bound. Likewise, one can prove that it satisfies the third law. In three dimensions, the situation is rather different: assuming the dominant energy condition, although one can prove a third law for the extremal BTZ black hole, one can still form it in collapse.