Abstract
We classify the stability region, marginal stability walls (MS) and split attractor flows for two-center extremal black holes in four-dimensional N = 2 supergravity minimally coupled to n vector multiplets. It is found that two-center (continuous) charge orbits, classified by four duality invariants, either support a stability region ending on an MS wall or on an anti-marginal stability (AMS) wall, but not both. Therefore, the scalar manifold never contains both walls. Moreover, the BPS mass of the black hole composite (in its stability region) never vanishes in the scalar manifold. For these reasons, the “bound state transformation walls” phenomenon does not necessarily occur in these theories. The entropy of the flow trees also satisfies an inequality which forbids “entropy enigma” decays in these models. Finally, the non-BPS case, due to the existence of a “fake” superpotential satisfying a triangle inequality, can be treated as well, and it can be shown to exhibit a split attractor flow dynamics which, at least in the n = 1 case, is analogous to the BPS one.
Highlights
The entropy of the flow trees satisfies an inequality which forbids “entropy enigma” decays in these models
Depending on the sign of some invariants, we have found that marginal stability walls (MS) or anti-marginal stability (AMS) walls can occur in the scalar manifold, but not both
The analysis carried out for minimally coupled Maxwell-Einstein supergravity is rather different from the one holding for N = 2 special Kahler geometries based on cubic prepotential [7], even though it exhibits many general properties of the split attractor flow for multi-center BHs
Summary
The corresponding split dynamics of the scalar flows exhibits a different behavior with respect to the N = 2 models with special Kahler geometry based on cubic prepotentials In these latter models, MS and AMS walls are known to co-exist, for a suitable choice of the charge vectors Q1 and Q2, in different zones of the scalar manifold itself As a consequence of (2.43)-(2.48), the inequality (2.50) (and its non-BPS counterpart (2.51)) implies that Z (W ) never vanishes in the scalar manifold, neither for single-center nor for two-center solutions For this reason, and for the fact that MS and AMS walls cannot co-exist in the scalar manifold, the “paradox” which led to the introduction of “bound state transformation walls” [8] does not occur in the class of theories under consideration. In cubic special geometries “bound state recombination walls” and “entropy enigma” decays are possible, respectively because (2.50) (with I2 replaced by I4) and (2.44) do not necessarily apply
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
