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arXiv · hep-th/9703156

U-Invariants, Black-Hole Entropy and Fixed Scalars

L. Andrianopoli·R. D'Auria·S. Ferrara
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Abstract

The absolute (moduli-independent) U-invariants of all N>2 extended supergravities at D=4 are derived in terms of (moduli-dependent) central and matter charges. These invariants give a general definition of the ``topological'' Bekenstein-Hawking entropy formula for extremal black-holes and reduce to the square of the black-hole ADM mass for ``fixed scalars'' which extremize the black-hole ``potential'' energy. The Hessian matrix of the black-hole potential at ``fixed scalars'', in contrast to N=2 theories, is shown to be degenerate, with rank (N-2)(N-3) + 2 n (N being the number of supersymmetries and n the number of matter multiplets) and semipositive definite.

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L. Andrianopoli, R. D'Auria, S. Ferrara. 1997-03-23. U-Invariants, Black-Hole Entropy and Fixed Scalars. https://doi.org/10.1016/s0370-2693(97)00454-1

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