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Anti de Sitter Black Holes. Harvey Reall University of Nottingham. Motivation. Black hole entropy calculations all rely on 2d CFT Can we calculate BH entropy using higher dimensional CFT? Need supersymmetric AdS black holes to evade strong coupling problem. Plan.
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Anti de Sitter Black Holes Harvey Reall University of Nottingham
Motivation • Black hole entropy calculations all rely on 2d CFT • Can we calculate BH entropy using higher dimensional CFT? • Need supersymmetric AdS black holes to evade strong coupling problem
Plan • SUSY asymptotically flat black holes • SUSY AdS black holes in D=3,4 • SUSY AdS black holes in D=5 • CFT interpretation • Collaborators: J. Gutowski, R. Roiban, H. Kunduri, J. Lucietti
SUSY 5D black holesHSR 02, Gutowski 03 • 5D supergravity + vectors • Introduce coordinates adapted to horizon • Impose supersymmetry • Near-horizon geometry fully determined
SUSY horizons: S3, S1 x S2, T3 • Only asymptotically flat SUSY BH with S3 horizon is BMPV • SUSY black rings discovered recently Elvang et al 04, Bena & Warner 04, Gauntlett & Gutowski 04 • T3 seems unlikely
SUSY AdS Black Holes • D=3: BTZ is SUSY black hole iff M=|J|>0 • D=4: Kerr-Newman-AdS (M,J,Q,P) saturates BPS bound if M=M(Q), J=J(Q), P=0 Kostalecky & Perry 95, Caldarelli & Klemm 98 • SUSY AdS black holes must rotate
5D SUSY AdS Black holesGutowski & HSR 04 • Reduce IIB SUGRA on S5 to N=1 D=5 U(1)3 gauged SUGRA Cvetic et al 99 • Canonical form for SUSY solutions involves specifying 4d Kähler “base space” Gauntlett & Gutowski 03, Gutowski & HSR 04 • Choice of base space not obvious e.g. get AdS5 from Bergman manifold • Try to find SUSY black holes systematically by examining near-horizon geometry
In near horizon limit, conditions for SUSY reduce to equations on 3-manifold • General solution unknown but particular S3 solution can be found • Use this to guess form of base space of corresponding black hole solution • First examples of SUSY AdS5 black holes • Preserve 1/16 SUSY • Cohomogeneity 1, 3 parameters • SO(6) R-charge (Q1,Q2,Q3), J1=J2=J(Q), BPS relation M=|J1|+|J2|+|Q1|+|Q2|+|Q3|
Unequal Angular Momenta • Chong, Cvetic, Lü & Pope 05: SUSY black holes with unequal angular momenta • Cohomogeneity 2, 2 parameters • Kunduri, Lucietti & HSR 06: most general known SUSY solution • parameterized by J1, J2, Q1, Q2, Q3 with one constraint • Expect non-BPS generalization with independent M,J,Q (2 more parameters)
A Puzzle • Why do BPS black holes have a constraint relating J,Q? • Is there a more general family of SUSY black holes with independent J,Q? • But then must have a more general family of non-BPS black holes: specifying M,Q,J not enough to determine topologically S3 black holes!
CFT entropy calculation? • Need to count 1/16 BPS states of N=4 SU(N) SYM on RxS3 (or local operators on R4) with same quantum numbers O(N2) as black hole • Black hole entropy O(N2) • States typically descendents but need large entropy O(N2) in primaries
No 1/8 BPS black holesRoiban & HSR 04, Berenstein 05 • 1/8 BPS primaries built from N=1 superfields Xi,W • Commutators give descendents, so Xi, W can be treated as commuting • Diagonalize: O(N) degrees of freedom so entropy of primaries of length O(N2) is O(N log N), too small for bulk horizon
Weakly coupled CFTRoiban & HSR 04, Kinney, Maldacena, Minwalla & Raju 05 • Goal: at weak coupling, count operators in short 1/16 BPS multiplets that can’t become long at strong coupling • Too hard! Count everything instead… • Find correct scaling of entropy with charge for large charge
Superconformal IndexKinney, Maldacena, Minwalla & Raju 05 • Vanishing contribution from states in short multiplets that can combine into long ones • Independent of N at large N: doesn’t “see” black holes • Cancellation between bosonic and fermionic BPS states dual to black hole
Summary • There is a 4-parameter family of 1/16 BPS black holes in AdS5 • Why only 4 parameters? • How do we calculate their entropy using N=4 SYM?