On the existence of non-supersymmetric black hole attractors for two-parameter Calabi-Yau's and attractor equations

We look for possible nonsupersymmetric black hole attractor solutions for type II compactification on (the mirror of) CY3(2, 128) expressed as a degree-12 hypersurface in WCP4[1, 1,2, 2, 6]. In the process, (a) for points away from the conifold locus, we show that the existence of a non-supersymmetric attractor along with a consistent choice of fluxes and extremum values of the complex structure moduli, could be connected to the existence of an elliptic curve fibered over C-8 which may also be "arithmetic" (in some cases, it is possible to interpret the extremization conditions for the black-hole superpotential as an endomorphism involving complex multiplication of an arithmetic elliptic curve), and (b) for points near the conifold locus, we show that existence of non-supersymmetric black-hole attractors corresponds to a version of A(1)-singularity in the space Image(Z(6) -> Z(2)/R-2 (hooked right arrow R-3)) fibered over the complex structure moduli space. The (derivatives of the) effective black hole potential can be thought of as a real (integer) projection in a suitable coordinate patch of the Veronese map: CP5 -> CP20, fibered over the complex structure moduli space. We also discuss application of Kallosh's attractor equations (which are equivalent to the extremization of the effective blackhole potential) for nonsupersymmetric attractors and show that (a) for points away from the conifold locus, the attractor equations demand that the attractor solutions be independent of one of the two complex structure moduli, and (b) for points near the conifold locus, the attractor equations imply switching off of one of the six components of the fluxes. Both these features are more obvious using the attractor equations than the extremization of the black hole potential. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.