Classical and Quantum Black Holes Le Studium, Tours, May 30-31, 2016 Black hole thermodynamics from a variational principle: Asymptotically conical background
Mirjam Cvetič
Ok Song An, M.C., Ioannis Papadimitriou, 1602.0150, JHEP03 (2016)086 Asymptotically flat or anti-deSitter (cosmological constant Λ < 0) spacetimes have been studied extensively, but new asymptotic backgrounds, asymptotically supported by matter fields, attracted attention only relatively recently.
Examples: ii. Flux vacua of string compactification, dual to certain supersymmetric quantum field theories (Klebanov-Strassler) ii. Lifshitz black holes, dual to certain non-relativistic quantum mechanical condensed systems iii. `Subtracted geometry’, proposed to addressed microscopics of certain non-extremal black holes.
Understanding the mesoscopic (geometric) properties of black holes with such exotic asymptotics à a first step towards their microscopic description. While black hole entropy & temperature is not sensitive to the asymptotics, as they are intrinsically connected with the horizon, conserved charges and the free energy depend on the spacetime asymptotics and receive contribution from asymptotic matter fields.
E.g., large distance divergences, plaguing conserved charges and free energy may not be always remedied by, say, Komar integral or background subtraction.
Main motivation: formulating well posed variational problem for new asymptotic geometries (following lessons from AdS geometries Heningson,Skenderis’98; Balasubramanian,Kraus’99; deBoer,Verlinde 2 ’99, … ) : to determine conserved charges & black hole thermodynamics.
Approach general (does not rely on the specific theory or its asymptotic solutions), but apply to concrete example of subtracted geometry. Summay: variational problem for new asymptotic geometries
Achieved through an algorithmic procedure:
• integration constants, parameterizing solutions of the eqs. of motion, separated into `normalizable’ - free to vary & ‘non-normalizable’ modes – fixed
• non-normalizable modes – fixed only up to transformations induced by local symmetries of the bulk theory (radial diffeomorphisms & gauge transformations)
• covariant boundary term, Sct, to the bulk action - determined by solving asymptotically the radial Hamilton-Jacobi eqn. à total action S+Sct independent of the radial coordinate
Skenderis,Papadimitriou’04,Papadimitriou’05 • first class constraints of Hamiltonian formal. lead to conserved charges associated with Killing vectors. [Sct ‘renormalizes’ the phase space: charges are independent of the radial coordinate.]
• Conserved charge automatically satisfy the first law of thermodynamics Outline:
I. Microscopics of Black Hole Entropy & String Theory
II. Motivation and review of subtracted geometry: Classical geometry insights Summary of quantum aspects
III. Thermodynamics: via variational principle Key Issue in Black Hole Physics:
How to relate Bekenstein-Hawking - thermodynamic entropy: Sthermo=¼ Ahor (Ahor= area of the black hole horizon; c=ħ=1;GN=1) to Statistical entropy: Sstat = log Ni ?
Where do black hole microscopic degrees Ni come from?
Horizon
Space-time singularity In String theory, main progress on microscopic origin of entropy primarily for extreme black holes w/
M = Σ |Q | + Σ | P | (schematic) i i i i M-mass, Qi-electric charges, Pi-magnetic charges Extreme à primarily supersymmetric (BPS) multi-charged black holes, J=0 & w/ Λ=0. Maldacena’97
Systematic study of microscopic degrees quantified via: AdSD/CFTD-1 (Gravity/Field Theory) correspondence
[ A string theory on a specific Curved Space-Time (in D-dim.) related to specific Field Theory (in (D-1)-dim.) on its boundary]
Specific microscopic examples of black holes in string theory: relation to 2-dim. CFT via AdS3/CFT2 correspondence extensively explored:
- supersymmetric (BPS) multi-charged black holes w/ Λ=0:
M = Σ |Q | + Σ | P | J=0 Strominger, Vafa’96.. i i i i (prototype: four-charge BPS dyon M.C., Youm 0507090) - near-BPS l black holes: M ~ Σ |Q | + Σ | P | Maldacena, Strominger’97.. i i i i - near-BPS multi-charged rotating black holes M.C., Larsen’98
Further developments: - (near-)extreme rotating black holes 2 M > Σi |Qi | + Σi| Pi|, but M =J Kerr/CFT correspondence Guica,Hartman,Song, Strominger’08 - extreme AdS charged rotating black holes in diverse dim. ….M.C., Chow, Lü, Pope 0812.2918 How about Microscopics of Non-extreme Black Holes?
M > Σi |Qi | + Σi| Pi |
Motivation for Subtracting Geometry Subtracted Geometry - Motivation
Introduced to quantify `past observations’ (later) M.C., Larsen ‘97-’99 that not only extreme, but also non-extreme black holes might have microscopic explanation in terms of dual 2-dim. QFT: focus on non-extreme asymptotically flat (Λ=0), charged ,rotating black holes in four (and five) dimensions.
Should focus on the black hole `by itself’ à enclose the black hole in a box (à la Gibbons Hawking), thus creating an equilibrium system with manifest conformal symmetry (later)
The box leads to a `mildly’ modified geometry changing only the warp factor Δ0à Δ
Subtracted Geometry M.C., Larsen 1106.3341,1112.4856
Non-extreme black holes in string theory w/ Λ=0
M - mass, Qi, Pi - multi-charges, J - angular momentum w/ M > Σi |Qi| + Σi| Pi |
Prototype solutions of a sector of maximally supersymmetric D=4 Supergravity [effective action of toroidally compactified string theory] à so-called STU model
2TheSTUmodelanddualityframes 2TheSTUmodelanddualityframes In this section we review the bosonic sector of the 2-charge truncation of the STU model that is In this section we review the bosonic sector of the 2-charge truncation of the STU model that is relevant for describing the subtracted geometries. We will do so in the duality frame discussed in relevant for describing the subtracted geometries. We will do so in the2TheSTUmodelanddualityframes duality frame discussed in [14], where both charges are electric, as well as in the one used in [17],[14], where where there both is one charges electric are and electric, as well as in the one used in [17], where there is one electric and one magnetic charge. We will refer to these frames as ‘electric’ andone ‘magnetic’In magnetic this section respectively. charge. we review We As will it the refer bosonic to these sector frames of the 2-chargeas ‘electr tic’runcation and ‘magnetic’ of the STU respectively. model that As is it will become clear from the subsequent analysis, in order to comparewill therelevant become thermodynamics for clear describing from in the the twothe subsequent subtracted analysis, geometries. in order We will to cdoompare so in the the duality thermodynamics frame discussed in the in two frames, it is necessary to keep track of boundary terms introducedframes, by[14], the duality it where is necessary transformations. both charges to keep are electric, track of as boundary well as in the terms one intro usedduced in [17], by where the there duality is one transformations. electric and one magnetic charge. We will refer to these frames as ‘electric’ and ‘magnetic’ respectively. As it 2.1 Magnetic frame 2.1will Magnetic become clear frame from the subsequent analysis, in order to compare the thermodynamics in the two frames, it is necessary to keep track of boundary terms introduced by the duality transformations. The bosonic Lagrangian of the STU model in the duality frame usedThe in bosonic [17] is given Lagrangian by of the STU model in the duality frame used in [17] is given by 1 1 2 2ηa a a 2.1 Magnetic frame 1 1 2κ4 4 = R ⋆ 1 ⋆ dηa dηa e ⋆ dχ dχ 2 κ STU2 = RModel⋆ 1 Lagrangian⋆ dη dη e 2ηa ⋆ dχa dχa L − 2 ∧ − 2 ∧ 4L4 − 2 a ∧ a − 2 ∧ 1 η0 0 0 1 2ηa η0 a a 0 Thea bosonica 0 [A Lagrangian sector of toroidally of the STU compactified model in the effective duality string frame theory] used in [17] is given by e− ⋆ F F e − ⋆ (F + χ F ) (F + χ F ) 1 η0 0 0 1 2ηa η0 a a 0 a a 0 − 2 ∧ − 2 ∧ e− ⋆ F F e − ⋆ (F + χ F ) (F + χ F ) 2 − 2 1 ∧ − 2 1 2ηa a a ∧ 1 a b c 1 a b 0 c 1 a b c 0 2κ0 4 4 = R ⋆ 1 ⋆ dηa dηa e ⋆ dχ dχ + Cabcχ F F + Cabcχ χ F F + Cabcχ χ χ F F , L 1(2.1)− 2a b ∧c 1− 2 a b 0 ∧ c 1 a b c 0 0 2 ∧ 2 ∧ 6 ∧ + Cabcχ F F + Cabcχ χ F F + Cabcχ χ χ F F , (2.1) 1 η0 0 0 1 2ηa η0 a a 0 a a 0 3 2 e− ⋆ F ∧ F 2 e − ⋆ (F ∧+ χ F 6) (F + χ F ) ∧ where ηa (a =1, 2, 3) are dilaton fields and η0 = a=1 ηa.ThesymbolCabc is pairwise symmetric− 2 ∧ − 2 3 ∧ with C =1andzerootherwise.TheKaluza-Kleinansatzforobtaininwhere ηagthisactionfromthe(a =1, 2, 3) are dilaton1 fields and η10 = a=1 ηa.Thesymbol1 Cabc is pairwise symmetric 123 ! + C χaF b F c + C χaχbF 0 F c + C χaχbχcF 0 F 0, (2.1) 6-dimensional action (1.1) is given explicitly in [17]. Thisframepossessesanexplicittrialitysym-with C123 =1andzerootherwise.TheKaluza-Kleinansatzforobtaininabc abc abc gthisactionfromthe 2 ∧ 2 ! ∧ 6 ∧ metry, exchanging the three gauge fields Aa,thethreedilatonsηa 6-dimensionaland the three axions actionχa.Inthis (1.1) is given explicitly in [17]. Thisframepossessesanexplicittrialitysym- where η (a =1, 2, 3) are dilaton fields and η = 3 η .ThesymbolC is pairwise symmetric frame, the subtracted geometries source all three gauge fields Aa magnetically,metry, exchanginga whilew/ A 0 the &is electri- three gauge fields Aa,thethreedilatons0 a=1 a ηa and theabc three axions χa.Inthis with C =1andzerootherwise.TheKaluza-Kleinansatzforobtainingthisactionfromthe cally sourced. Moreover, holographic renormalization turns out toframe, be much the more123 subtracted straightforward geometries source all three! gauge fields Aa magnetically, while A0 is electri- 6-dimensional action (1.1) is given explicitly in [17]. Thisframepossessesanexplicittrialitysym- in this frame compared with the electric frame. cally sourced. Black Moreover, holes: holographic explicit solutions renormalization of equations turns of out motion to be for much the above more straightforward metry, exchanging Lagrangian the three w/ metric, gauge fields fourA gaugea,thethreedilatons potentials andηa threeand the axio-dilatons three axions χ a.Inthis In order to describe the subtracted geometries it suffices toin consider this frame a truncation compared of (2.1), with the electric frame. a 0 frame,1 the2 subtracted3 geometries source all three gauge fields A magnetically, while A is electri- corresponding to setting η1 = η2 = η3 η, χ1 = χ2 = χ3 χ,andA = A = A A.The ≡ ≡ Incally order sourced. to Prototype, describe Moreover,≡ the four-charge holographic subtracted renormalization rotating geometries black it tur su holensffices out, originally to to cbeonsider much obtained more a truncation straightforward via of (2.1), resulting action can be written in the σ-model form 1 2 3 correspondingin this frame solution to compared setting generatingη with1 = theη2 = electrictechniquesη3 frame.η, χ 1 = χ 2 = χ 3 χ ,and M.C.,A Youm= A 9603147= A A.The 1 1 ≡ Chong,≡ M.C., Lü, Pope 0411045 ≡ S = d4x√ g R[g] ∂ ϕI ∂µϕJ F Λ F Σµν resultingϵµνρσInF action orderΛ F Σ to can+ describeS be, written(2.2) the subtracted in the σ-model geometries form it suffices to consider a truncation of (2.1), 4 2 IJ µ ΛΣ µν ΛΣ µν ρσ Four- GHSO(1,1) transfs. cosh i sinh i 2κ4 − − 2G − Z − R H = , 1 2 (34)3 "M # corresponding1 $ to setting η1 = 1η2 = η3 sinhη , χ1cosh= χ2 = χ3 χ,andA = A = A A.The S = dtime-reduced4x√ g R [Kerrg] BH ∂ ✓ϕ≡I ∂µϕi J i ◆F Λ F Σ≡µν ϵµνρσF Λ F Σ +≡S , (2.2) where 4resulting2 action can be written inIJ theµσ-model formΛΣ µν ΛΣ µν ρσ GH 2correspondsκ4 to: − − 2G − Z − R 1 3 "M # $ SGH = d x√ γ 2K, Full four-electric(2.3) and four-magnetic charge solution only recently obtained 2 1 4 2 1 I2 µ J Λ Σµν µνρσ Λ Σ 2κ4 ∂ − where x p 1+ ↵ x 0 1 p 1+ ↵ x Chow, Compère 1310.1295;1404.2602 " M S4 = 2y 0 =d y,√ g e R[g] = ⇤ IJe ∂µϕ ∂, ϕ ΛΣFµν F ΛΣϵ Fµν Fρσ + SGH, (2.2) 2κ − − 2G 1 − Z3 − R is the standard Gibbons-Hawking [36] term and we have defined the doublets 4 1 2p1+↵2x 2 2 x√ 2 2 2p1+↵2x 0"M= ⇤ [ +# (eSGH = (12 + ↵ ) d)] ; ⇤ =(γ 2 K,+ 1) e . (35)$ (2.3) where p1+↵2 2κ4 ∂ − η A0 " M ϕI = ,AΛ = ,I=1, 2, isΛ the=1 standard, 2, Gibbons-Hawking(2.4) [36] term1 and we have3 defined the doublets χ A Note, this transformation can also beSGH determined= 2 as and analyticx√ γ continuation2K, of transformations (2.3) # $ # $ given in Section 2 of [19]. A Harrison transformation2κ4 ∂ in the limit− of an infinite boost corresponds η A" 0M as well as the 2 2matrices is theto standard 1 5. In Gibbons-Hawking theϕ caseI = of ↵ =,A1 [36], we term shallΛ = act and with we,I (33) have on defined the=1 Schwarzschild, 2,theΛ doublets=1 solution, 2, with (2.4) × ! χ p3 A 30 1 e 3η +3e ηχ2 3e ηχ e12U =1χ3 23mχ,2 = 0, = 0. The transformation (34) with =1resultsin⇤ = 2m , and the − − − 2r # $ # 0$ r IJ = 2η , ΛΣ = η η , ΛΣ =metric3 (6)2 with the. subtracted(2.5)I η geometry warpΛ factor:A G 03e Z 4 3e− χ 3e− asR well as4 theχ 2 3χ2matricesϕ = ,A= ,I=1, 2, Λ =1, 2, (2.4) # $ # $ # 2 × $ χ A # $ 3η4 # η $2 3 η 3 3 2 30 1 se0 = r +3 es =(2χ m)3r,e χ 1 χ(36) χ As usual, ϵµνρσ = √ g εµνρσ denotes the totally antisymmetric Levi-Civita tensor, where εµνρσ = − ! − − 2 − asIJ well= as the2 2η ,2matricesΛΣ = η η , ΛΣ = 3 2 . (2.5) 1istheLevi-Civitasymbol.ThroughoutthispaperwechoosetheG orientation03e in × so thatZ 4 3e− χ 3e− R 4 χ 3χ ± and# the30 scalar$M field and the electric1# fielde strength3η +3e : ηχ2 3e ηχ $ 1 #χ23 3 χ2 $ εrtθφ =1.WenoteinpassingthattheLagrangian(2.2)isinvariantunder= the global symmetry, = − − − , = 2 . (2.5) As usual,IJ ϵµνρσ = √2η g εµνρσ ΛΣdenotes the totallyη antisymmetricη Levi-CivitaΛΣ tensor,3 2 where εµνρσ = transformation G 03e Z 24 2m3e− χ 2 3e−1 R 4 2 χ 3χ − p3 1istheLevi-Civitasymbol.Throughoutthispaperwechoose# $ e #= , Ftr = ,$ the orientation# (37) in$ so that η 2 η 2 0 3 0 2 2 r 3 2m e µ e , χ µ− χ,A µ A ,A µA,± As ds usual,ds ,ϵµνρσ = √ g(2.6)εµνρσ denotesr the totallyr antisymmetric Levi-Civita tensor, whereMεµνρσ = → → → → εrtθφ =1.WenoteinpassingthattheLagrangian(2.2)isinvariant→ − under the global symmetry 1istheLevi-Civitasymbol.Throughoutthispaperwechoosei.e., this is the static subtracted geometry of Subsection 2.1, with ⇧c =1, ⇧thes = orientation 0. in so that where µ is an arbitrary non-zero constant parameter. transformation± The subtracted geometry for the Kerr spacetime can be obtained by reducing the spacetime M εrtθφ =1.WenoteinpassingthattheLagrangian(2.2)isinvariantunder the global symmetry on the time-likeη Killing2 η vector and acting2 on the0 Kerr black3 0 hole with an infinite boost2 Harrison2 transformatione µ e , χ µ− χ,A µ A ,A µA, ds ds , (2.6) transformation→ for Lagrangian density→ (1), where→ we set 1 = 2 =→ 3 , '1 =→'2 = '3 5 η 2 η 2 0 3 0 ⌘ 2 2 ⌘ where µ2is , anF arbitrary= F e= non-zeroµ e , 2 Fχ constantandµ− χ=,A parameter.p2 , i.e.µ anA Einstein-Dilaton-Axion,A µA, ds gravityds , with (2.6) p3 ⇤ 1 2 →⇤F1 ⌘ 3 → F2 F → → → two U(1) gauge fields and respectiveq dilaton couplings ↵ = 1 and ↵ = p3. The subtracted where µ is an arbitrary non-zero constant parameter.1 p3 2 geometry of the multi-charged rotating black holes is expected to arise as a specific Harrison transformation on a rotating charged black solution5 of (1). We defer technical aspects of these calculations to follow-up work. 5
3 Asymptotically Conical Metrics 3.1 Lifshitz Scaling The scaling limit, or equivalently the subtraction process, alters the environment that our black holes find themselves in [12, 13]. In fact the asymptotic metrics take the form
R 2p ds2 = dt2 + B2dR2 + R2 d✓2 +sin2 ✓2d 2) (38) R0 with B and R0 constants. In our case B = 4 and p = 3. In general metrics with asymptotic form (37) may be referred as Asymptotically Conical (AC). The spatial metric is conical because the radial distance BR is a non-trivial multiple of the area distance R. Restricted to the equatorial plane the spatial metric is that of a flat two-dimensional cone
2 2 2 2 2 dsequ = B dR + R d (39)
5One may verify that (33) with b 1intheEinstein-Maxwellgravity(↵ =0)takestheSchwarzschildmetric to the Robinson-Bertotti one. This! type of transformation was employed recently in [21]. For another work, 2 relating the Schwarzschild geometry to AdS2 S ,see[22]. ⇥
10 Metric of rotating four-charge black holes in String Theory: M.C. & Youm 9603147 Chong, M.C., Lü & Pope 0411045
= 0 outer & inner horizon
Special cases: Mass δI = δ Kerr-Newman & a = 0 Reisner-Nordström; Four charges δI = 0 Kerr & a = 0 Schwarzschild; Angular momentum δIà∞ mà0 w/m exp(2δI)-finite Or equivalently : m, a, δI (I=0,1,2,3) extremal (BPS) black hole Thermodynamics - suggestive of weakly interacting 2-dim. CFT w/ `left-’ & `right-moving’ excitations first noted, M.C., Youm’96 M.C., Larsen’97 Area of outer horizon S = S + S 2 2 + L R SL =S⇡L m= ⇡(⇧mc +(⇧⇧cs+)(1)⇧s)(1) [Area of inner horizon S = S – S ] S p⇡ m2pm22 a2 - L R SR = ⇡R m= m 2 a2 (⇧c (⇧⇧cs)(2)⇧s)(2) SL S=L ⇡=m⇡ m(⇧ (c⇧+c +⇧s⇧)(1)s )(1) L =2 L⇡=2m (⇡⇧mc (⇧⇧cs)(3)⇧s)(3) 2 2 2 2 Surface gravity (inverse temperature) ofS S=R ⇡=m⇡pmmpm a a(⇧ (⇧c ⇧ ⇧)(2)s)(2) R 2⇡ m22⇡ m2 c s = (⇧ + ⇧ )(4) R R = 2 2 c (⇧cs+ ⇧s)(4) outer horizon βH = ½ (βL + βR ) Lp =2mL =2p⇡mm⇡a2(m⇧(ca⇧2 c ⇧s⇧)(3)s)(3) ⇧ = ⇧ =03 cosh3 ,Pi2 2 = ⇧ =03 sinh3 (5) c ⇧c I= ⇧I =0 cosh2I⇡2m⇡ Im,Pis sI= ⇧I =0 sinhI I (5) [inner horizon β- = ½ (βL - βR ) ] R =R = (⇧(c⇧+c +⇧s⇧)(4)s)(4) HW 7, Phys 151 pmp2m2 a2 a2 HW 7, Phys 151 3 3 3 3 Similar structure for angular ⇧velocities=⇧c⇧= ⇧=0ΩI, =0 Ωcosh andcosh momenta,Pi I ,Pi J=,s J=⇧. ⇧ =0I =0sinhsinh I (5)(5) Ch. 29: c I + - I s + - I I Ch. 29: Exercises:HW 7, 2,6,11,13,16,20,23,37 Phys 151 DependHW onlyExercises: 7,on four Phys parameters: 151 2,6,11,13,16,20,23,37 m, a, Problems: 2,7 Problems: 2,7 Ch. 29: Shown moreCh. recently, 29: all independent of the warp factor Δ ! HWExercises: due on Wednesday, 2,6,11,13,16,20,23,37 October 22nd. o Exercises:HW due 2,6,11,13,16,20,23,37 on Wednesday, October 22nd.M.C., Larsen’11 Problems: 2,7 Problems:Reminder: 2,7Next Midterm is on Thursday, October 23rd, 11 AM in A1. Reminder: Next Midterm is on Thursday, October 23rd, 11 AM in A1. HW due on Wednesday, October 22nd. HWHW due and on other Wednesday, information October available 22nd. on: http://www.physics.upenn.edu/phys151.htlmHW and other information available on: Reminder:(orReminder: equivalentlyhttp://www.physics.upenn.edu/phys151.htlmNextNext at Midterm http://www.physics.upenn.edu/ Midterm is on is on Thursday, Thursday, October October cvetic) 23rd, 23rd, 11 11 AM AM in in A1. A1. (or equivalently at http://www.physics.upenn.edu/ cvetic) HWHW and and other other information information available available on: on: http://www.physics.upenn.edu/phys151.htlmhttp://www.physics.upenn.edu/phys151.htlm (or(or equivalently equivalently at http://www.physics.upenn.edu/ at http://www.physics.upenn.edu/ cvetic) cvetic) Determination of new warp factor Δ0 à Δ via massless scalar field wave eq.: wave eq. separable & the radial part is solved by hypergeometric functions w/ SL(2,R)2 (manifest conformal symmetryà promoted to 2-dim. CFT)
(with warp factor Δ0 implicit):
w/
Δ à Δ such that wave eq. is separable: f(r)+g( θ ) (true for Δ and Δ) 0 0
& the radial part is solved by hypergeometric functions:
uniquely fixed f(r)+g(θ)-const.
M.C., Larsen 1112.4856 Subtracted geometry for rotating four-charge black holes
4 Comments: while Δ0 ~ r , Δ ~ r subtracted geometry depends only on four parameters: m, a, Remarks:
Asymptotic geometry of subtracted geometry is of a Lifshitz-type w/ a deficit angle:
p=3, B=4
à black hole in an ``asymptotically conical box’’ (w/ deficit angle) M.C., Gibbons 1201.0601
à the box is confining (``softer’’ than AdS) 2TheSTUmodelanddualityframes
In this section we review the bosonic sector of the 2-charge truncation of the STU model that is relevant for describing the subtracted geometries. We will do so in the duality frame discussed in [14], where both charges are electric, as well as in the one used in [17], where there is one electric and one magnetic charge. We will refer to these frames as ‘electric’ and ‘magnetic’ respectively. As it will become clear from the subsequent analysis, in order to compare the thermodynamics in the two 2TheSTUmodelanddualityframesframes, it is necessary to keep track of boundary terms introduced by the duality transformations.
In this section we review the bosonic sector of the 2-charge truncation of the STU model that is 2.1 Magnetic frame relevant for describing the subtracted geometries. We will do so in the duality frame discussed in [14], where both charges are electric,The as well bosonic as in the Lagrangian one used in of [17], the where STU there model is onein the electric duality and frame used in [17] is given by one magnetic charge. We will refer to these frames as ‘electric’ and ‘magnetic’ respectively. As it 2 1 1 2ηa a a will become clear from the subsequent analysis, in2κ order4 4 = toR compare⋆ 1 the⋆ d thermodynamicsηa dηa e in⋆ thedχ two dχ frames, it is necessary to keep track of boundary termsL introduced− 2 by the duality∧ − transformations.2 ∧ 1 η0 0 0 1 2ηa η0 a a 0 a a 0 e− ⋆ F F e − ⋆ (F + χ F ) (F + χ F ) 2.1 Magnetic frame − 2 ∧ − 2 ∧ 1 1 1 + C χaF b F c + C χaχbF 0 F c + C χaχbχcF 0 F 0, (2.1) The bosonic Lagrangian of the STU model in the duality frame2 uabcsed in [17]∧ is given2 byabc ∧ 6 abc ∧ 1 1 3 2 where ηa (a2=1ηa , 2,a3) area dilaton fields and η0 = ηa.ThesymbolCabc is pairwise symmetric 2κ4 4 = R ⋆ 1 ⋆ dηa dηa e ⋆ dχ dχ a=1 L − 2 with∧ C−1232 =1andzerootherwise.TheKaluza-Kleinansatzforobtainin∧ gthisactionfromthe 1 1 ! η0 0 0 2ηa η0 3Asymptoticallyconicalbackgroundsa a 0 a a 0 e− ⋆ F 6-dimensionalF e − action⋆ (F + (1.1)3Asymptoticallyconicalbackgroundsχ F is) given(F + explicitlyχ F ) in [17]. Thisframepossessesanexplicittrialitysym- − 2 metry,∧ − exchanging2 the three gauge∧ fields Aa,thethreedilatonsηa and the three axions χa.Inthis 1 a b c 1 a b 0The generalc 1 rotatinga b subtractedc 0 0 geometry backgroundsa are solutions of the equations0 of motion + Cabcχ F frame,F + theCabc subtractedχ χ F F geometries+ Cabcχ sourceχ χ F allF three, gauge(2.1) fields A magnetically, while A is electri- 2 ∧ 2 following∧ The from6 general the action rotating (2.2)∧ subtractedor (2.10) and take geometry the form backgrounds [14, 17]5 are solutions of the equations of motion cally sourced. Moreover, holographic renormalization turns out toM.C., be Gibbons much 1201.0601 more straightforward 3 following from the action (2.2) or (2.10) and take the form [14, 17]5 where ηa (a =1, 2, 3) are dilaton fields and η0 = Matterηa.Thesymbol fields (gaugeCabc is potentials pairwise symmetric and scalars) in this frame compareda=1 2 with√∆ the2 electricG frame.2 2 X 2 2 with C =1andzerootherwise.TheKaluza-Kleinansatzforobtaininds = dr¯ gthisactionfromthe(dt¯+ ) + √∆ dθ + sin θdφ¯ , 123 In order to3Asymptoticallyconicalbackgrounds describe theX subtracted− √∆ geometriesA it suffiGces to consider a truncation of (2.1), ! √∆ G ! " X 6-dimensional action (1.1) is given explicitly in [17]. Thisframepossessesanexplicittrialitysym-2 2 2 2 2 1 2 2 ¯2 3 corresponding to Scalars: settingη dsη(21 m==) η2 =drη¯3 a (Πηc, χ(Π1dst¯=) +χ2 )=+χ3√∆χ,anddθ +A =sinAθd=φ A , A.The metry, exchanging the three gauge fields Aa,thethreedilatonsThe generale = rotatingηa and, X the subtractedχ three= −≡ axions√ geometry∆− χa.Inthiscos backgroundsAθ, ≡ are solutionsG of the equations≡ of motion resulting action can be written√∆ in the σ-model2m form 5 frame, the subtracted geometries source all three gaugefollowing fields fromAa themagnetically, action (2.2) while or (2.10)A0 andis electri- take the form! [14, 17] " 4 (2m)2 a (Π 2 Π 2) 2 4 0 (2ηm) a (Πc Πs) 2 ¯ (2mac ) coss θ (Πc Πs) +(2m) ΠcΠs ¯ cally sourced. Moreover, holographic renormalization1 4 turnsA out=e to= be1 much− , moreIsin straightforwardµχθd=Jφ + −Λ Σcosµν 2 θ−, 2 µνρσ Λ Σdt, S4 = d x√ √g ∆R[g] G√∆ IJ∂µϕ ∂ ϕ ΛΣ2mFX F (Πc ΠsΛΣ) ∆ϵ F F + SGH, (2.2) in this frame compared with the electric frame.2 ds2 = dr¯2 (∆dt¯+ )2 + √∆ dθ2 + µνsin2 θdφ¯2− , µν ρσ 2κ4 − 2m cos− θ2G − Z − R "M X# − √∆ 4 A 2 2 G2 ¯ 2 2 $ 2 ¯ 4 In order to describe the subtracted geometries it suffiAces= to consider(2m∆) aa (2( truncationΠma) (Πc !) ofΠs (2.1),) sin θ dφ(2ma2"ma) (2cosmΠsθ+¯(rΠ(Πc ΠΠs))) d+(2t , m) Π Π where 20 ∆ − c s− 2 ¯ − c − s c s ¯ Gaugeη (2 potentials:mA) = 1 a (Πc 2 Π−s) 3 sin θdφ + − dt, corresponding to setting η1 = η2 = η3 η, χ1 = χ2e==χ3 χ,,and1 χA#$= = A∆(2−ma=1)A2(cosΠ θ,AΠ.The) % (2ma)2(Π Π )[2(mΠΠ2 +¯Πr(2Π) ∆Π& )] cos2 θ ≡ A√≡=∆ r¯ Sm =2m ≡c −d3sx√dt¯γ+ 2K, c − s c s s c − s (2.3)dt¯ resulting action can be written in the σ-model form 2m GH (2m)23(Π + Π ) 2m∆− −4 2m−cos−θ 2κ4 ∂c 2s 2− 2 4 (2m) a (Πc! Πs) "(2ma) cos2" θ (Πc Πs2) +(22 m) Π¯cΠs ¯ 1 1 0 A = 2 ∆¯ (2Mma) (Πc Π(2s)masin)2(Πθ dΠφ)2 cos2¯ma2 θ (2mΠs +¯r(Πc Πs)) dt , 4 I µ J A Λ= 'Σµν − µνρσsinΛ θdΣφ + 2 2 − 2 c s dt, ¯ S4 = d x√ g R[g] isIJ the∂µϕ standard∂ ϕ ΛΣ Gibbons-HawkingF F ∆ ΛΣϵ [36]∆ F termF+ a and(−Π+c S weGHΠs, have)sin(2.2)θ defined(Π−1+ Π the) ∆ doublets− − dφ, (3.1)− 2 µν µν ρσ − c − s ∆ 2κ4 − − 2G − Z − R 2 ! 2 " 2 "M # 2m cos θ 1 2#$ $ 0(22ma2) (Π¯c Πs) % (2ma) (Πc Πs)[2mΠs +¯r(Πc Π&s)] cos θ A = I A =η ∆ (2mar¯)Λ(Πmc AΠs) sin θ dφ 2ma (2mΠdt¯s ++¯r(Πc Πs)) dt¯ , dt¯ where whereϕ ∆= ,A= ,I3 =1−, 2, Λ =1, 2, − (2.4) − χ −−2m − −−A (2m) (Πc −+ Πs) − 2m∆ 1 3 ! 2 2 " 2 SGH = d x√ γ 2K,1 ##$$ (2ma) (Πc# Πs$) (2.3)% (2ma) (Πc Πs)[2mΠs +¯r(Πc 2 Π&s)] cos θ 2 2 2 A = 2r¯ m 2 − d2t¯+ 2 −2ma Magnetic(2 maframe)− (Π Π2 )dt¯¯cos θ as well2κ as4 the∂ 2 2matrices− −X2m=¯'r −2m−r¯ +(2am,G)3(Π +=ΠX) a sin θ, = 2 ((Π2mc ∆Πs)¯r +2mΠcs)sin sθdφ, ¯ " M × ! − c s −"+ a(Πc ΠsA)sinGθ 1+− − dφ, (3.1) is the standard Gibbons-Hawking [36] term and we have defined the3 doublets2 23η 4η 22 η 2−(2ma)2(Π2 Π2 )2 cos2 θ 3 3 2 ∆ 30' w/ ∆ =(2m) (Π1c eΠ−s)¯r +(2+3me−) Πχs 2 (23ema− )χ(Πc Πs) c cos sθ, 1 χ ¯ χ (3.2) − + a(Πc Πs)sin−θ 1+ − − ! dφ,2 (3.1) " IJ = 0 2η , ΛΣ = −η η , ∆ΛΣ = 3 2 . (2.5) I η G Λ A03e Z 4 3e χ 3e R 4 χ 3χ ϕ = ,A= ,Iand=1whereΠ ,, 2Π, , aΛand=1m, 2are, parameters− of the(2.4)! solution.− 2 " χ #A $ c s # $ # $ where In order to study the thermodynamics of these backgrounds it is necessary to identify which # $ As usual,#ϵµνρσ$ = √ g εµνρσ denotes the totally antisymmetric Levi-Civita tensor,2 whema re εµνρσ = as well as the 2 2matrices parameters− are fixed2 by the boundary2 conditions in the2 variat2 ional problem. A full analysis of the 2 ¯ 1istheLevi-Civitasymbol.Throughoutthispaperwechoose2 X =¯r 2 2mr¯ + a ,G2 2 = X a2masintheθ, orientation= in ((2Πsoc¯ thatΠs)¯r +2mΠs)sin θdφ, × Xvariational=¯r 2m problemr¯ + a ,G for the= actionsX a (2.2)sin θ or, (2.10)= require((sknowledgeofthegeneralasymptoticΠc Πs)¯r +2mΠGs)sin θdφ, ± 3η η 2 η − 3 3 2 − G A M − 30 1εrteθφ− =1.WenoteinpassingthattheLagrangian(2.2)isinvariant+3e− χ 3e− χ − 13 χ2 2−χ2 4 A2 under2− the global2 2 symmetry IJ = 2η , ΛΣ = η solutionsη , and3∆ =(22 isΛΣ beyond=m2 ) ( theΠ3 2 scope4 Π2 of)¯r the.+(2(2.5) present2m) Π paper.2 (2 Howevma2 ) er,(Π wec canΠs consider) cos theθ, variational (3.2) G 03e Z 4transformation3e− χ 3∆e−=(2m) (ΠRc Πs)¯r4+(2χcm) Π3sχs (2ma) (Πc Πs s) cos θ, (3.2) # $ # problem$ within− the class# of2 stationary− −$ solutions (3.1).− − To this end, it is− convenient to reparameterize η 2 η 2 0 3 0 2 2 As usual, ϵµνρσ = √ g εµνρσ denotes the totally antisymmetricand Πthese, Π backgrounds, a and Levi-Civitam are by parameters means tensor, of whe a of suitablere theεµ solution.νρσ coordinate= transformation, accompanied by a relabeling − e c andµs e Π, c, χΠs, aµ−andχ,Am are parametersµ A ,A of theµA, solution. ds ds , (2.6) 1istheLevi-Civitasymbol.ThroughoutthispaperwechooseInof→ order the free to study parameters.the→ the orientation thermodynamics In particular, in → weso of introduce thatthese backgrounds→ the new coordinates it is→ necessary to identify which ± where µ is an arbitrary non-zeroIn order constant to study parameter. theM thermodynamics of these backgrounds it is necessary to identify which εrtθφ =1.WenoteinpassingthattheLagrangian(2.2)isinvariantparameters are fixed byunder the4 boundary the global3 conditions symmetry2 2 in the variat4 2 ional problem.2 A2 full analysis of the parameters areℓ r fixed=(2m by) (Π thec boundaryΠs)¯r +(2m) conditionsΠs (2ma) ( inΠc theΠs variat) , ional problem. A full analysis of the transformation variational problem for the actions (2.2)− or (2.10) requiresknowledgeofthegeneralasymptotic− − k 1 2ma(Π Π ) solutionsvariational and is beyond problem the scope for of the the present actions¯ paper. (2.2) Howev¯ orer, (2.10) we canc require considers ¯ sknowledgeofthegeneralasymptotic the variational η 2 η 2 0 3 0 2 3 t =2 3 2 2 t, φ = φ 3 2− 2 t, (3.3) e µ e , χ µ− χ,A µ A ,A µA, ds ℓ ds ,(2m) (Π5c Π(2.6)s) − (2m) (Πc Πs) → → → problem withinsolutions→ the class and of→ is stationary beyond solutions the− scope (3.1). of To the this present end, it is paper.convenient− Howev to reparameterizeer, we can consider the variational where µ is an arbitrary non-zero constant parameter.thesewhere backgroundsproblemℓ and k byare within means additional the of a class suitablenon-zero of stationary coordinate parameters, transfo whosesolutionsrmation, role will (3.1). accompanied become To tclearhis byend, shortly. a relabeling it Moreover,is convenient to reparameterize of thewe free definethese parameters. the backgrounds new parameters In particular, by means we introduce of a suitable the new c coordinateoordinates transformation, accompanied by a relabeling 4 3 2 2 4 2 2 2 of the free4 ℓ parameters.r =(23m) (2Π In2Π particular,)¯r +(2m2 ) Π we(2 introduce2ma) (Πc2 theΠ2s) , new3 c2oordinates2 5 ℓ r =(2m) m(Πc +c Πs) s (2ma) (Πc s Πs) m a (2m) (Πc Πs), ± − − −− ± −− − 3 k 1 2ma(Πc Πs) ℓ ω =2t ma= (Πc Πs4),Bt,¯ =23m,φ =2 φ¯ 2 ( 4 t,¯2 2 (3.3)(3.4)2 3 −3 2 2 3 2− 2 ℓ (2m) (Πℓc r =(2Πs) m) (Πc −Π(2s)¯mr)+(2(Πc mΠ)s)Πs (2ma) (Πc Πs) , 5 − − − − − In order to compare this backgroundk with the expressions1 given in eqs. (24) and (25) of [14],2ma one( shouldΠ takeΠ into) whereaccountℓ and thek are field additional redefinition non-zeroA →−A, χ parameters,→−χ,beforethedualizationof whose role will¯ becomeA, as mentionedclear¯ shortly. in footnote Moreover,c 4, and adds a¯ 3 t = 3 2 2 t, φ = φ 2 2 ¯ 3 2− 2 t, (3.3) we defineconstant the pure new gauge parameters term. Moreover,ℓ there is(2 am typo) in(Π eq. (25Π)of[14]:theterm2) mΠs−cos(2θdmt should) (Π be replacedΠ ) − 2 ¯ c s c s by 2mΠs(Πs Πc)cos θdt. − − 4 3 2 2 2 2 2 2 3 2 2 whereℓ r =(2ℓ andm) km(areΠc + additionalΠs) (2ma) non-zero(Πc Πs) parameters,m a (2 whosem) (Πc roleΠs will), become clear shortly. Moreover, ± − − ± − − 3 weℓ defineω =2ma the(Πc newΠs parameters),B=2m, ( (3.4) − 5In order to compare this background with the expressions given in eqs. (24) and (25) of [14], one should take into 4 3 2 27 2 2 2 2 3 2 2 account the field redefinitionℓ Ar →−=(2A, χm→−) mχ,beforethedualizationof(Πc + Πs) (2maA), as(Π mentionedc Πs) in footnotem 4, anda add(2 am) (Πc Πs), ± 2 2 constant pure gauge term. Moreover, there is a typo in eq. (25)of[14]:theterm2− m−Πs cos θd±t¯ should be− replaced − 2 3 by 2mΠs(Πs − Πc)cos θdt¯. ℓ ω =2ma(Πc Πs),B=2m, ( (3.4) − 5In order to compare this background with the expressions given in eqs. (24) and (25) of [14], one should take into account the field redefinition A →−A, χ →−χ,beforethedualizationofA, as mentioned in footnote 4, and add a 2 2 constant pure gauge term. Moreover, there is a typo in eq. (25)of[14]:theterm2mΠs cos θdt¯ should be replaced 2 by 2mΠs(Πs − Πc)cos θdt¯. 7
7 The quantities β , β and β are removed by a gauge transformation φ φ+(β +β +β )t. 1 2 3 −→ 1 2 3 We shall assume from now on that this transformation has been performed. The final metric The quantities β , β and β are removed by a gauge transformation φ φ+(β +β +β )t. can be cast in the1 following2 3 form: −→ 1 2 3 We shall assume from now on that this transformation has been performed. The final metric X F 2dr2 F 2 sin2 θ 2 √ 2 √ 2 2 can be castds in= the∆ following2 dt form:+ 2 + ∆dθ + (dφ + Wdt) , (6.22) F !− X " √∆ X F 2dr2 F 2 sin2 θ where 2 √ 2 √ 2 2 ds = ∆ 2 dt + 2 + ∆dθ + (dφ + Wdt) , (6.22) F !− X " √∆ where X = r2 2mr , − 2 2 3 2 2 2 F X=(2= rm) 2mr(Πc , Πs)r +(2m)Πs , − − 4 2 16m3#ΠsΠ2 cβ4 2 2 $ WF =(2m) (Πc Πs,)r +(2m)Πs , = 2 − − 16m#4FΠ Π β $ W 2 s 6 c 24 , 2 2 ∆ ==F +(2m2) β (Πc Πs) sin θ . (6.23) − F 4 − 2 6 2 2 2 ∆ = F +(2m) β4 (Πc Πs) sin θ . (6.23) The dilation fields are of the form: − The dilation fields are of the form: Q eφ1 eϕ2 eϕ3 , = = = Q (6.24) eφ1 = eϕ2 = eϕ3 = √∆, (6.24) √∆ and the axion fields vanish. The Kaluza-Klein U(1) gauge field becomes and the axion fields vanish. The Kaluza-Klein U(1) gauge field becomes 3 3 2 2 2 2 Q 2mΠcΠs Q (2m) β (Π Π )sin θ Q3 m Q3 m 2β 4 2c 2s 2 θ 2 = 2 2 Π2 cΠ2s dt (2 ) 4(Πc −Πs)sin dφ+ , (6.25) A 2 =(Πc 2 Πs)2F 2 dt− ∆− dφ+ , (6.25) A (Π−c Πs)F − ∆ − −1 where Q is defined in (6.5) and φ+ = φ + Ω+t,withΩ+ = β4ΠcΠ−1s .Theremainingthree where Q is defined in (6.5) and φ+ = φ + Ω+t,withΩ+ = β4ΠcΠs .Theremainingthree gaugegauge potentials potentials become become identified identified and and are are of of the the form form (6.3) (6.3) b bysettingysettinga a=0.=0. OneOne can can of of course course remove removeQQinin the the scalar scalar and and gauge gauge fields fields via via a a gauge gauge transformation. transformation. However,However, it is it useful is useful to to keep keep it it in in the the discussion discussion of the the lift. lift.
6.36.3 Subtracted Subtracted Geometry Geometry Lifted Lifted to to Five Five Dimensions Dimensions We now provide a lift of the subtracted rotating geometry to five-dimensions5.Thefive- We now provide a lift of the subtracted rotating geometry to five-dimensions5.Thefive- dimensional metric for the scaling limit takes the form: dimensional metric for the scaling limit takes the form: M.C., Larsen 1112.4856 Lift of subtracted geometry on circle S1 to five-dimension turns out to 2 ϕ1 2 −2ϕ1 2 locallyds5 = e factorizeds4 + e AdS(dz x+ S2 2 )([SL(2,R), 2 x SO(3)]/Z symmetry)(6.26) 2 ϕ1 2 −2ϕ1 3 A 2 2 ds 5 = e ds4 + e (dz + 2) , (6.26) where we have to implement the scaling z zϵ−1.Thismetrictakestheform:A [globally S2 fiberedwith over Bañados-Teitelboim-Zanelli (BTZ) black hole → −1 where we have to implement the scaling z zϵ .Thismetrictakestheform:16ma(Πc Πs) -3 w/ mass M−32, angular momentum J3 &φ¯ 3dφ cosmol. const. Λz =lt ], 2 3 → 2 2 = + 3 − ( + ) (6.29) ds5 = ϵ (dsS2 + dsBTZ) , ℓ (6.27) with − 2 2 3 and2 2 ds5 = ϵ (dsS2 + dsBTZ) , 16ma(Πc Πs) (6.27) φ¯ =2 φ +2 2 2 − (z + t) , 2 2 (6.29) where (r r )(r r 3−) ℓ r r r − ds2 3 −with3+ 3 − ℓ3 dt2 3 dr2 r2 dφ 3+ 3 dt 2 , BTZ = 2 2 3 + 2 2 2 2 3 + 3( 3 + 2 3) 2 1 2 2 2− ¯2 ℓ r (r r )(r 16rma−()Πc Πs) ℓr where anddsS2 = 4 ℓ dθ +sin θdφ , 3 3 φ¯3+=(6.28)φ +3 3 − (z + t) , 3 (6.29) − − ℓ3 (6.30) 5 2% 2 2 2 & 2 2 Partial results were provided in2 [5, 9].1 Here(2r wer2 take)(r particu2 r −¯)2lar care of theℓ dimensionsr and of the r r − ds2 2 = ℓ 3 dwhereθ 3++sin3 θ3dφ and2, 3 2 (6.28)2 3+ 3 2 dsBTZS = 4 − 2 − dt3 + 2 2 2 2 dr3 + r3(dφ3 + 2 dt3) , ℓ2 r r r 2 r2 r2 2 2 ℓ2r periodicities of metric coordinates. − 3 ( 3 (r3+)(r3 )(r 3−)r −) ℓ r 3 r r − 5 % &dsz2 − 3 − 3+− 3 − 3 dt2 3 dr2 r2 dφ 3+ 3 dt 2 , Partial results were provided in [5, 9]. Here we take particularBTZ care= of the dimensions2 2 and3 + of the2 2 2 2 (6.30)3 + 3( 3 + 2 3) φ3 = , − ℓ r (r r )(r r −) ℓr R 3 3 − 3+ 3 − 3 3 periodicities of metric coordinates.where 23 ℓ (6.30) t3 = t, z whereR 2 φ3 = , 2 16(2mR) z2 2 2 2 2 2 23R r3 = φ2m=(Πc , Πs)r +(2m) Πs a (Πc Πs) . (6.31) ℓ4 3 − − − ℓ ! R " Conformal t symmetryt, of AdS can be promotedℓ to Virasoro algebra1 3 = 3 1 2 2 3 Here,R R is the size of the circlet3 S= andt, ℓ =4m(Πc Πs) is the radius of the AdS3. of dual two-dimensional2 CFT R à la Brown-− Hennaux 2 Furthermore16(2mR) 2 2 16(22 mR2 )2 2 2 Standard statisticalr = entropy2m ( (viaΠ AdSΠ )r3+(2/CFT2 m2)) Π a ( Π c 2 Π às )la2 Cardy. 2 2(6.31)2 2 3 4 c smRr3 = s 2m(Πc Πs)r +(2m) Πs a (Πc Πs) . (6.31) ℓ − 8 ℓ4 − 2−− 2 − − à Reproduces entropy! ofr3± 4D= blackm(Π holesc + Πs) ! m a (Π"c Πs) . (6.32)" ℓ2 1 1 1 # 2 2 ±3 1 − − 2% 2 Here, R is the size of the circle Here,S andR isℓ the=4 sizem(Π ofc theΠ circles) $isS theand radiusℓ =4m of(Π thec Π AdSs) 3 3is. the radius of the AdS3. The periodicity of z coordinate is 2πR,andthustheangularcoordinate− − φ3 has the correct Furthermore Furthermore periodicity of 2π.Notealsothatthe2π periodicitymR of φ¯ is ensured if 16ma(Π Π )ℓ−3 is mR 8 2 2 c s 8 r23± = 2 m(Πc + Πs) m a (Πc Π−s) . (6.32) r3± = m(Πc −+ Πs) m a (ℓΠ2 c Πs) . (6.32) quantized inℓ2 units of R 1. ± − −# ± $ − − % # $z πR % φ The periodicity of coordinate is 22 ,andthustheangularcoordinate 3 has the correct The periodicity of z Thecoordinate lifted geometry is 2πR,andthustheangularcoordinate is indeed locally AdS3 S with theφ3 radiushas the of correct AdS3 equal to ℓ and −3 periodicity of 2π.Notealsothatthe2× π periodicity of φ¯ is ensured if 16ma(Πc Πs)ℓ is 2 ℓ −3 periodicity of 2π.Notealsothatthe2the radius of S equalπ toperiodicity. of φ¯ is ensured if 16ma(Πc Πs)ℓ is − quantized2 in units of R−1. − −1 quantized in units of R . 2 Subtracted MagnetisedThe lifted Geometry geometry is indeed locally AdS3 S with the radius of AdS3 equal to ℓ and 2 × The lifted geometry is indeed locally AdS3 2 S withℓ the radius of AdS3 equal to ℓ and the radius of S equal to 2 . This geometry also lifts to (6.27)× where now φ¯ in (6.28) is defined as6 the radius of S2 equal to ℓ . 2 Subtracted Magnetised Geometry φ¯ = φ + β4 z, (6.33) Subtracted Magnetised GeometryThis geometry also lifts to (6.27) where now φ¯ in (6.28) is defined as6 and we set in all expressions above a =0,i.e.theBTZcoordinatesarerelatedto t, r, z 6 { } This geometry also lifts to (6.27) where now φ¯ in (6.28) is defined asφ¯ = φ + β4 z, (6.33) as in (6.31) with a =0.(Obviously,β4 =0correspondstotheliftofthestaticsubtracted −1 geometry.) Note thatand thewe¯ set shift in requiresall expressions that β above4 be quantizeda =0,i.e.theBTZcoordinatesarerelatedto in units of R ,inorderforφ¯ t, r, z φ = φ + β4 z, (6.33) { } to have the correctas periodicity in (6.31) with of 2aπ=0.(Obviously,. β4 =0correspondstotheliftofthestaticsubtracted and we set in all expressions above a =0,i.e.theBTZcoordinatesarerelatedto t, r, z −1 ¯ geometry.) Note that the shift requires that β4 be quantized{ in} units of R ,inorderforφ as in (6.31) with 6.4a =0.(Obviously, Relation ofto havetheβ4 =0correspondstotheliftofthestaticsubtracted BTZ the correct Black periodicity Hole Coordinates of 2π. to the AdS3 Coordinates −1 geometry.) Note that the shift requires that β4 be quantized in units of R ,inorderforφ¯ According to [14, 15] AdS3 is the quadric 6.4 Relation of the BTZ Black Hole Coordinates to the AdS3 Coordinates to have the correct periodicity of 2π. u2 + v2 x2 y2 = ℓ2 , (6.34) According to [14, 15] AdS−3 is the− quadric 6It was observed in [25] that such a shift produces a magnetic field for the Kaluza-Klein U(1) gauge 6.4 Relation of the BTZ Black Hole Coordinates to the AdS3 Coordinates u2 + v2 x2 y2 = ℓ2 , (6.34) potential and thus a four-dimensional geometry in a Kaluza-Klein− magnetic− field. 6It was observed in [25] that such a shift produces a magnetic field for the Kaluza-Klein U(1) gauge According to [14, 15] AdS3 is the quadric potential and thus a four-dimensional24 geometry in a Kaluza-Klein magnetic field. u2 + v2 x2 y2 = ℓ2 , (6.34) − − 24 6It was observed in [25] that such a shift produces a magnetic field for the Kaluza-Klein U(1) gauge potential and thus a four-dimensional geometry in a Kaluza-Klein magnetic field.
24 order to demonstrate the procedure we shall present the details for the Schwarzschild black hole, only. In this case it is su cient to employ the Einstein-Dilaton-Maxwell Lagrangian density, with the dilation coupling ↵ = 1 , which is a consistent truncation of the Lagrangian density p3 (1) with = 0, ' = ' = ' 2 , F = F = 2 F and = 0. [Of course for i i 2 3 ⌘ p3 ⇤ 1 2 ⇤F1 ⌘ 3 F2 the multi-charged rotating black holes one has to employ the fullq N=2 supergravity Lagrangian density (1).] We begin by considering static solutions to general Einstein-Dilaton-Maxwell equations with the general dilation coupling ↵. The Lagrangian density is 4.:
1 1 2 1 2↵ 2 p g R (@ ) e F . (24) 4 2 4 ⇣ Making the Ansatz 2 2U 2 2U i j ds = e dt + e dx dx ,F= @ (25) ij i0 i we obtain an e↵ective action density in three dimensions of the form
ij 2U 2↵ p R( ) 2 @ U@ U + @ @ e e @ @ (26) ij i j i j i j ⇣ ⇣ ⌘⌘ Defining U + ↵ ↵U + x ,y , (27) ⌘ p1+↵2 ⌘ p1+↵2 the e↵ective action density becomes
ij 2p1+↵2x p R( ) 2 @ x@ x + @ y@ y e @ @ . (28) ij i j i j i j ⇣ ⇣ ⌘⌘ Evidently we can consistently set y = 0 and we obtain a sigma model, whose fields x, map into the target SL(2, R)/SO(1, 1), coupled to three dimensional Einstein gravity. The non-trivial action of an SO(1, 1) subgroup of SL(2, R) is called a Harrison transformation. More concretely, and following [19] but making some changes necessitated by considering a reduction on time-like, rather than a space-like Killing vector we define a matrix (See also, e.g., [20] and references therein.):
2p1+↵2x 2 2 2 p1+↵2(x+y) e (1 + ↵ ) p1+↵ P = e , (29) p1+ ↵2 1 ✓ It is straightforward to◆ show that a Harrison transformation: so that T 2p1+↵2y 10 P = P , det P = e . (30) H = , (34) 1 Taking H SO(1, 1) which acts on P as ✓ ◆ 2 P HPHT corresponds, to: (31) ! p1+↵2x0 1 p1+↵2x it preserves not only the properties (30) but also the Lagrangiany0 = densityy, (28) e which can= be⇤ caste , in the form: Further insights into geometry of subtracted1 geometry 2p1+ ↵2x 2 2 2 2 2p1+↵2x 1 ij 0 1 = ⇤ [ + (e (1 + ↵ ) )] ; ⇤ =( + 1) e . (35) p R( )+ Tr(@ P @ P ) . p1+↵2 (32) ij 1+↵2 i j It is straightforward i. Subtracted to show geometry that⇣ a Harrison as an transformation: infiniteNote, boost this Harrison transformation⌘ transformations can also be determined as an analytic continuation of transformations on the original BH,SO(1,1) transformationsgiven in Section [change 2 of aysmptotics [20]. A Harrison] transformation in the limit of an infinite boost corresponds 10 M.C. & Gibbons 1201.0601 H to, 1. One may verify that (34) with(33) 1 in the Einstein-Maxwell gravity (↵ = 0) takes the ⇠ 1 ! Virmani 1203.5088 ! ✓ ◆ Schwarzschild Sahay metric & Virmani to the 1305.2800 Robinson-Bertotti.. one. This type of transformation was employed 4 2 We choose the units in which 4⇡G =1.NotethatintheLagrangiandensity(1)16recently in [22]. For another⇡G =1andthefield work, relating the Schwarzschild geometry to AdS2 S , see [23]. strengths di↵er by a factor of p2. In the case of ↵ = 1 , we shall act with (34) on the Schwarzschild solution with⇥e2U =1 2m , ii. Interpolating geometries between the original black holep3 r 2m and their subtracted geometries obtained:= 0, = 0. The transformation (35) with =1resultsin⇤ = r , and the metric (6) with 9 - via solution generating techniquesthe subtracted geometry warp factor: