An extremization principle for the entropy of rotating BPS black holes in AdS5

We show that the Bekenstein-Hawking entropy of a class of BPS electrically charged rotating black holes in AdS(5) x S-5 can be obtained by a simple extremization principle. We expect that this extremization corresponds to the attractor mechanism for BPS rotating black holes in five-dimensional gauged supergravity, which is still unknown. The expression to be extremized has a suggestive resemblance to anomaly polynomials and the supersymmetric Casimir energy recently studied for N = 4 super Yang-Mills.