IIB black hole horizons with fiveform flux and KT geometry
Abstract
We investigate the near horizon geometry of IIB supergravity black holes with nonvanishing 5form flux preserving at least two supersymmetries. We demonstrate that there are three classes of solutions distinguished by the choice of Killing spinors. We find that the spatial horizon sections of the class of solutions with an SU(4) invariant pure Killing spinor are hermitian manifolds and admit a hidden Kähler with torsion (KT) geometry compatible with the SU(4) structure. Moreover the Bianchi identity of the 5form, which also implies the field equations, can be expressed in terms of the torsion dleft( {ω wedge H} right) = partial bar{partial }{ω^2} = 0 , where ω is a Hermitian form. We give several examples of near horizon geometries which include group manifolds, group fibrations over KT manifolds and uplifted geometries of lower dimensional black holes. Furthermore, we show that the class of solutions associated with a Spin(7) invariant spinor is locally a product {mathbb{R}^{1,1}} × mathcal{S} , where mathcal{S} is a holonomy Spin(7) manifold.
 Publication:

Journal of High Energy Physics
 Pub Date:
 May 2011
 DOI:
 10.1007/JHEP05(2011)050
 arXiv:
 arXiv:1101.1247
 Bibcode:
 2011JHEP...05..050G
 Keywords:

 Black Holes in String Theory;
 Supergravity Models;
 High Energy Physics  Theory
 EPrint:
 32 pages, latex. Minor corrections to section 5