Supersymmetric black holes and Freudenthal duality

We study the effect of Freudenthal duality on supersymmetric extremal black hole attractors in [Formula: see text], [Formula: see text] ungauged supergravity. Freudenthal duality acts on the dyonic black hole charges as an anti-involution which keeps the black hole entropy and the critical points of the effective black hole potential invariant. We analyze its effect on the recently discovered distinct, mutually exclusive phases of axionic supersymmetric black holes, related to the existence of nontrivial involutory constant matrices. In particular, we consider a supersymmetric [Formula: see text] black hole and we explicitly Freudenthal-map it to a supersymmetric [Formula: see text] black hole. We thus show that the charge representation space of a supersymmetric [Formula: see text] black hole also contains mutually exclusive domains.

PARTITION FUNCTION OF NON-SUPERSYMMETRIC BLACK HOLES IN THE SUPERGRAVITY LIMIT

In this paper, we propose a free energy for general non-supersymmetric black hole attractors (with vanishing D0-brane charge) arising in type IIA(B) superstrings on 3-fold Calabi–Yau, in the supergravity limit. This, by definition, differs from its counterpart BPS free energy by a factor of 4. Correspondingly, a mixed ensemble for these black holes is proposed.