230 likes | 248 Views
Anti de Sitter Black Holes. Harvey Reall University of Nottingham. Motivation. Black hole entropy calculations all rely on 2d CFT Can we use AdS/CFT to calculate entropy of D>3 AdS black holes? D=4: probably not, CFT not understood D=5: CFT is N =4 SYM…
E N D
Anti de Sitter Black Holes Harvey Reall University of Nottingham
Motivation • Black hole entropy calculations all rely on 2d CFT • Can we use AdS/CFT to calculate entropy of D>3 AdS black holes? • D=4: probably not, CFT not understood • D=5: CFT is N=4 SYM… • Need supersymmetric AdS5 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 04 • 5D ungauged N=1 sugra + abelian vectors • Introduce coordinates adapted to horizon • Take near-horizon limit • Impose supersymmetry: eqs on spatial cross-section of horizon • Can determine general solution for compact horizon
SUSY 5D black holesHSR 02, Gutowski 04 • All possible near-horizon geometries: • Which arise from asymp flat black holes? • Near-horizon BMPV from BMPV! • AdS3xS2 from BPS black rings Elvang et al 04 • Flat T3 horizon unlikely Galloway 06
SUSY AdS Black Holes • BPS limit of Reissner-Nordstrom-AdS is nakedly singular • 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 SU(2,1)/U(2)
5D SUSY AdS black holesGutowski& HSR 04 • Seek SUSY black holes systematically by examining near-horizon geometry • In near-horizon limit, conditions for SUSY are equations on 3-manifold • General solution not known • Particular homogeneous S3 solution can be found (cf near-horizon BMPV)
5D SUSY AdS black holesGutowski& HSR 04 • Near-horizon solution motivates cohomogeneity-1 Ansatz for full solution • First examples of SUSY AdS5 black holes! • Base space singular, cohomogeneity-1, asymptotically Bergman space • 1/16 BPS
Unequal Angular MomentaChong, Cvetic, Lü & Pope 05 • Guessed non-BPS charged rotating black hole solution of minimal gauged sugra (Einstein-Maxwell) • Cohomogeneity-2, 4 parameters (M,J1,J2,Q) • BPS limit: 2 parameter solution with J1≠J2
General solutionKunduri, Lucietti & HSR 06 • Determine base space of BPS solution of minimal gauged sugra: singular, cohomogeneity-2, asymptotically Bergman • Plug into BPS eqs of U(1)3 gauged sugra, solve… • BPS solution parametrized by J1, J2, Q1, Q2, Q3 with one constraint • Expect non-BPS generalization with independent M,J,Q (2 more parameters)
CFT description • BPS AdS5 black hole microstates are 1/16 BPS states of N=4 large N SYM on RxS3 (equivalently BPS local operators on R4) • States classified by SO(4)xSO(6) quantum numbers J,Q • Black hole quantum numbers O(N2) • Black hole entropy O(N2) • Entropy calculation: count all 1/16 BPS states with same quantum numbers as black hole
A Puzzle • 1/16 BPS states have independent J,Q • 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 corresponding non-SUSY solution would need more than just conserved charges to specify it • BPS AdS black rings?
BPS AdS black rings?Kunduri, Lucietti & HSR 06 • Most general BPS near-horizon geometry in 5D gauged sugra not known • Assume existence of 2 rotational symmetries (true for all known 5d black holes): problem reduces to ODEs. 2 interesting solutions. • One solution is near-horizon geometry of known S3 black holes • Another solution is a warped product AdS3xS2 with horizon topology S1xS2…
BPS AdS black rings?Kunduri, Lucietti & HSR 06 • …but with a conical singularity on S2 • Can’t eliminate singularity (without turning off cosmological constant) • BPS AdS black rings with 2 rotational symmetries do not exist • Oxidize to 10d: warped product AdS3xM7 with M7=S2xS5 (singular)
New 10d black holes? • Solution is locally isometric to AdS3xM7 solution of Gauntlett et al 06 • They showed that solution can be made globally regular by choosing topology of M7 appropriately (not S2xS5) • Resulting solution cannot be reduced to 5d • Could this be near-horizon geometry of an asymptotically AdS5xS5 black hole?
Resolutions of the puzzle? • Are there BPS 10d black hole solutions that can’t be reduced to 5d? • Are there BPS 5d black holes without 2 rotational symmetries? • Non-abelian BPS black holes? • Maybe we know most general black hole. 1/16 BPS states have 5 charges but perhaps only 4 charge subset has O(N2) entropy Berkooz et al 06
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?