Static supersymmetric black holes in AdS_4 with spherical symmetry

We elaborate further on the static supersymmetric AdS_4 black holes found in arXiv:0911.4926, investigating thoroughly the BPS constraints for spherical symmetry in N = 2 gauged supergravity in the presence of Fayet-Iliopoulos terms. We find Killing spinors that preserve two of the original eight supercharges and investigate the conditions for genuine black holes free of naked singularities. The existence of a horizon is intimately related with the requirement that the scalars are not constant, but given in terms of harmonic functions in analogy to the attractor flow in ungauged supergravity. The black hole charges depend on the choice of the electromagnetic gauging, with only magnetic charges for purely electric gaugings. Finally we show how these black holes can be embedded in N = 8 supergravity and thus in M-theory.Comment: 28 pages; v2 minor change

6d-5d-4d reduction of BPS attractors in flat gauged supergravities

Via a series of Kaluza-Klein (KK) and Scherk-Schwarz (SS) compactifications we relate BPS attractors and their complete (in general non-BPS) flows to a Minkowski vacuum in gauged supergravities with vanishing scalar potential in 4, 5, and 6 dimensions. This way we can look at a class of extremal non-BPS black holes and strings from IIB string theory viewpoint, keeping 4 supercharges on the horizon. Our results imply the existence of a dual 2d N = (0,2) superconformal field theory (SCFT) that originates from a parent N=(4,4) theory living on a D1-D5 system. This is achieved starting from the BPS black string in 6d with an AdS_3xS^3 attractor and taking two different routes to arrive at a 1/2 BPS AdS_2xS^2 attractor of a non-BPS black hole in 4d N=2 flat gauged supergravity. The two inequivalent routes interchange the order of KK reduction on AdS_3 and SS reduction on S^3. We also find the commutator between the two operations after performing a duality transformation: on the level of the theory the result is the exchange of electric with magnetic gaugings; on the level of the solution we find a flip of the quartic invariant I_4 to -I_4.Comment: 20 pages, 2 flow charts; v2 improved discussion and added referenc

Lessons from the Vacuum Structure of 4d N=2 Supergravity

This PhD thesis is devoted to the study of supersymmetry preserving background solutions of N=2 supergravity in 4 dimensions. The main contents are divided into three major parts, briefly summarized as follows. Part I deals with analysis of maximally supersymmetric configurations. Part II discusses BPS black holes with Minkowski and anti-de Sitter (AdS) asymptotics. The main topics in part III are superalgebras, BPS bounds and conserved charges for asymptotically flat or AdS spacetimes. Most of the chapters are based on previously published results with the exception of chapter 10 in part III, which is genuinely new and discusses the superalgebras of black hole configurations and their near-horizon geometries. A no-go theorem for static BPS black holes in AdS is proven in theories without hypermultiplets and the analogous situation in 5d is briefly explained.Comment: 209 pages; PhD thesis, defended 1 June 2012, advisor Stefan Vandoren; v2 minor correction

Ungauging black holes and hidden supercharges

We embed the general solution for non-BPS extremal asymptotically flat static and under-rotating black holes in abelian gauged D=4 N=2 supergravity, in the limit where the scalar potential vanishes but the gauging does not. Using this result, we show explicitly that some supersymmetries are preserved in the near horizon region of all the asymptotically flat solutions above, in the gauged theory. This reveals a deep relation between microscopic entropy counting of extremal black holes in Minkowski and BPS black holes in AdS. Finally, we discuss the relevance of this construction to the structure of asymptotically AdS4 black holes, as well as the possibility of including hypermultiplets.Comment: 33 pages, 1 figure, v2: Corrections in section 5, comments added, references update

Phase transitions of magnetic AdS4 black holes with scalar hair

We determine the thermodynamic properties of a class of spherically symmetric and static black holes in AdS4 with magnetic charges and scalar hair. These black holes are solutions in 4d N=2 gauged supergravity that can arise from eleven-dimensional supergravity compactified on S^7. At zero temperature, they preserve supersymmetry and hence are stable. At non-zero temperatures, we explore in detail the canonical ensemble and stability of solutions and find a first order phase transition between small and large hairy black holes. The transition emerges as a liquid-gas phase transition in the dual three-dimensional field theory on R x S^2 with magnetic flux through S^2.Comment: 5 pages, v2: misprints corrected and references added, published versio

An extremization principle for the entropy of rotating BPS black holes in AdS5_5

We show that the Bekenstein-Hawking entropy of a class of BPS electrically charged rotating black holes in AdS$_5\times S^5$ can be obtained by a simple extremization principle. We expect that this extremization corresponds to the attractor mechanism for BPS rotating black holes in five-dimensional gauged supergravity, which is still unknown. The expression to be extremized has a suggestive resemblance to anomaly polynomials and the supersymmetric Casimir energy recently studied for $\mathcal{N}=4$ super Yang-Mills.Comment: 27 pages; v2: refs added; v3: ref adde

Wilson lines for AdS_5 black strings

We describe a simple method of extending AdS_5 black string solutions of 5d gauged supergravity in a supersymmetric way by addition of Wilson lines along a circular direction in space. When this direction is chosen along the string, and due to the specific form of 5d supergravity that features Chern-Simons terms, the existence of magnetic charges automatically generates conserved electric charges in a 5d analogue of the Witten effect. Therefore we find a rather generic, model-independent way of adding electric charges to already existing solutions with no backreaction from the geometry or breaking of any symmetry. We use this method to explicitly write down more general versions of the Benini-Bobev black strings and comment on the implications for the dual field theory and the similarities with generalizations of the Cacciatori-Klemm black holes in AdS_4.Comment: 13 pages; v2 improved discussion, added reference

Spindle black holes in AdS4×_4 \timesSE7_7

We construct new classes of supersymmetric AdS$_2 \times {\Sigma}$ solutions of 4d gauged supergravity in presence of charged hypermultiplet scalars, with ${\Sigma}$ the complex weighted projective space known as a spindle. These solutions can be viewed as near-horizon geometries of asymptotically Anti de-Sitter (AdS$_4$) black holes with magnetic fluxes that admit embedding in 11d on Sasaki-Einstein (SE$_7$) manifolds, which renders them of holographic interest. We show that in each case the Bekenstein-Hawking entropy follows from the procedure of gluing two gravitational blocks, ultimately determined by SE$_7$ data. This allows us to establish the general form of the gravitational blocks in gauged 4d ${\mathcal N} =2$ supergravity with charged scalars and massive vectors. Holographically, our results provide a large N answer for the spindle index with anti-twist and additional mesonic or baryonic fluxes of a number of ${\mathcal N} =2$ Chern-Simons-matter theories.Comment: 40 pages, 2 figures, 1 Mathematica fil