Jackiw-Teitelboim Theory Research Articles

Jackiw-Teitelboim gravity and near-extremal BTZ thermodynamics

We study the near horizon 2D gravity theory which captures the near extremal thermodynamics of Banados-Teitelboim-Zanelli (BTZ) with excess mass $\ensuremath{\delta}M$ and excess angular momentum $\ensuremath{\delta}J=\mathcal{L}\ensuremath{\delta}M$ over extremality. We find that the Jackiw-Teitelboim theory is able to capture such departures from extremality with an additional parameter $\mathcal{L}$ relating it to the near extremal BTZ configuration. We are able to show this by obtaining new simultaneous near horizon near extremal limits of the BTZ geometry parametrized by $\mathcal{L}$. The resulting Jackiw-Teitelboim theory captures the near extremal thermodynamics of such BTZ geometries provided we identify the temperature ${T}_{H}^{(2)}$ of the ${\mathit{AdS}}_{2}$ geometry in the Jackiw-Teitelboim theory to be ${T}_{H}^{(2)}={T}_{H}/(1\ensuremath{-}\ensuremath{\mu}\mathcal{L})$, where ${T}_{H}$ is the BTZ temperature and $\ensuremath{\mu}$ its chemical potential with $\ensuremath{\mu}\mathcal{L}<1$.

JT gravity and near-extremal thermodynamics for Kerr black holes in AdS4,5 for rotating perturbations

We study the near horizon 2d gravity theory which captures the near extremal thermodynamics of Kerr black holes where a linear combination of excess angular momentum δJ and excess mass δM is held fixed. These correspond to processes where both the mass and the angular momenta of extremal Kerr black holes are perturbed leaving them near extremal. For the Kerr AdS4 we hold delta J-mathcal{L}delta M=0 while for Myers-Perry(MP) type Kerr black hole in AdS5 we hold delta {J}_{varphi 1,2}-{mathcal{L}}_{varphi 1,2}delta M=0 . We show that in near horizon, the 2d Jackiw-Teitelboim theory is able to capture the thermodynamics of the higher dimensional black holes at small near extremal temperatures TH. We show this by generalizing the near horizon limits found in literature by parameters mathcal{L} and {mathcal{L}}_{varphi 1,2} for the two geometries. The resulting JT theory captures the near extremal thermodynamics of such geometries provided we identify the temperature {T}_H^{(2)} of the near horizon AdS2 geometry to be {T}_H^{(2)}={T}_H/left(1-mu mathcal{L}right) for 4d Kerr and {T}_h^2={T}_H/left(-mu left({mathcal{L}}_{varphi 1}+{mathcal{L}}_{varphi 2}right)right) for 5d Kerr μ is their chemical potential, with mu mathcal{L}<1 and mu left({mathcal{L}}_{varphi 1}+{mathcal{L}}_{varphi 2}right)<1 respectively. We also argue that such a theory embeds itself non-trivially in the higher dimensional theorydual to the Kerr geometries.

JT gravity from holographic reduction of 3D asymptotically flat spacetime

We attempt to understand the CFT1 structure underlying (2+1)D gravity in flat spacetime via dimensional reduction. We observe that under superrotation, the hyperbolic (and dS2) slices of flat spacetime transform to asymptotically (A)dS2 slices. We consider a wedge region bounded by two such surfaces as End-of-the-World branes and employ Wedge holography to perform holographic reduction. We show that once we consider fluctuating branes, the localised theory on the branes is Jackiw-Teitelboim (JT) theory. Finally, using the dual description of JT, we derive an 1D Schwarzian theory at the spatial slice of null infinity. In this dual Celestial (nearly) CFT, the superrotation mode of 3D plays the role of the Schwarzian derivative of the boundary time reparametrization mode.

Large diffeomorphisms and accidental symmetry of the extremal horizon

We uncover a symmetry of the linear Einstein equations near extremal horizons. Specifically, acting with a spherically symmetric linearized diffeomorphism on the perturbative solutions to the Einstein-Maxwell equations in the Bertotti-Robinson background, but not acting on the background itself, we find that there is a subset of such transformations under which the equations of motion remain satisfied, with or without additional matter. This represents an “accidental” symmetry in the sense that the set of transformations realizing the mapping among solutions is strictly larger than the SL(2) isometries of the background spacetime. We argue that our accidental symmetry can be thought of as an on-shell large diffeomorphism of AdS2, which we support in the context of Jackiw-Teitelboim theory.

Semi-classical thermodynamics of quantum extremal surfaces in Jackiw-Teitelboim gravity

Quantum extremal surfaces (QES), codimension-2 spacelike regions which extremize the generalized entropy of a gravity-matter system, play a key role in the study of the black hole information problem. The thermodynamics of QESs, however, has been largely unexplored, as a proper interpretation requires a detailed understanding of backreaction due to quantum fields. We investigate this problem in semi-classical Jackiw-Teitelboim (JT) gravity, where the spacetime is the eternal two-dimensional Anti-de Sitter (AdS2) black hole, Hawking radiation is described by a conformal field theory with central charge c, and backreaction effects may be analyzed exactly. We show the Wald entropy of the semi-classical JT theory entirely encapsulates the generalized entropy — including time-dependent von Neumann entropy contributions — whose extremization leads to a QES lying just outside of the black hole horizon. Consequently, the QES defines a Rindler wedge nested inside the enveloping black hole. We use covariant phase space techniques on a time-reflection symmetric slice to derive a Smarr relation and first law of nested Rindler wedge thermodynamics, regularized using local counterterms, and intrinsically including semi-classical effects. Moreover, in the microcanonical ensemble the semi-classical first law implies the generalized entropy of the QES is stationary at fixed energy. Thus, the thermodynamics of the nested Rindler wedge is equivalent to the thermodynamics of the QES in the microcanonical ensemble.

Dilaton gravity with a boundary: from unitarity to black hole evaporation

We point out that two-dimensional Russo-Susskind-Thorlacius (RST) model for evaporating black holes is locally equivalent — at the full quantum level — to flat-space Jackiw-Teitelboim (JT) gravity that was recently shown to be unitary. Globally, the two models differ by a reflective spacetime boundary added in the RST model. Treating the boundary as a local and covariant deformation of quantum JT theory, we develop sensible semiclassical description of evaporating RST black holes. Nevertheless, our semiclassical solutions fail to resolve the information recovery problem, and they do not indicate formation of remnants. This means that either the standard semiclassical method incorrectly describes the evaporation process or the RST boundary makes the flat-space JT model fundamentally inconsistent.

Gravitational perturbations as [formula omitted]-deformations in 2D dilaton gravity systems

We consider gravitational perturbations of 2D dilaton gravity systems and show that these can be recast into TT¯-deformations (at least) under certain conditions, where T means the energy-momentum tensor of the matter field coupled to a dilaton gravity. In particular, the class of theories under this condition includes a Jackiw-Teitelboim (JT) theory with a negative cosmological constant including conformal matter fields. This is a generalization of the preceding work on the flat-space JT gravity by S. Dubovsky, V. Gorbenko and M. Mirbabayi [arXiv:1706.06604].

Complexity of Jackiw-Teitelboim gravity

The Jackiw-Teitelboim (JT) model arises from the dimensional reduction of charged black holes. Motivated by the holographic complexity conjecture, we calculate the late-time rate of change of action of a Wheeler-DeWitt patch in the JT theory. Surprisingly, the rate vanishes. This is puzzling because it contradicts both holographic expectations for the rate of complexification and also action calculations for charged black holes. We trace the discrepancy to an improper treatment of boundary terms when naively doing the dimensional reduction. Once the boundary term is corrected, we find exact agreement with expectations. We comment on the general lessons that this might hold for holographic complexity and beyond.

The gravitational dynamics of kinematic space

We show that the dynamics of the kinematic space of a 2-dimensional CFT is gravitational and described by Jackiw-Teitelboim theory. We discuss the first law of this 2-dimensional dilaton gravity theory to support the relation between modular Hamiltonian and dilaton that underlies the kinematic space construction. It is further argued that Jackiw-Teitelboim gravity can be derived from a 2-dimensional version of Jacobson’s maximal vacuum entanglement hypothesis. Applied to the kinematic space context, this leads us to the statement that the kinematic space of a 2-dimensional boundary CFT can be obtained from coupling the boundary CFT to JT gravity through a maximal vacuum entanglement principle.

Holographic complexity equals which action?

We revisit the complexity = action proposal for charged black holes. We investigate the complexity for a dyonic black hole, and we find the surprising feature that the late-time growth is sensitive to the ratio between electric and magnetic charges. In particular, the late-time growth rate vanishes when the black hole carries only a magnetic charge. If the dyonic black hole is perturbed by a light shock wave, a similar feature appears for the switchback effect, e.g. it is absent for purely magnetic black holes. We then show how the inclusion of a surface term to the action can put the electric and magnetic charges on an equal footing, or more generally change the value of the late-time growt rate. Next, we investigate how the causal structure influences the late-time growth with and without the surface term for charged black holes in a family of Einstein-Maxwell-Dilaton theories. Finally, we connect the previous discussion to the complexity=action proposal for the two-dimensional Jackiw-Teitelboim theory. Since the two-dimensional theory is obtained by a dimensional reduction from Einstein-Maxwell theory in higher dimensions in a near-extremal and near-horizon limit, the choices of parent action and parent background solution determine the behaviour of holographic complexity in two dimensions.

5D rotating black holes and the nAdS2/nCFT1 correspondence

We study rotating black holes in five dimensions using the nAdS2/nCFT1 correspondence. A consistent truncation of pure Einstein gravity (with a cosmological constant) in five dimensions to two dimensions gives a generalization of the Jackiw-Teitelboim theory that has two scalar fields: a dilaton and a squashing parameter that breaks spherical symmetry. The interplay between these two scalar fields is non trivial and leads to interesting new features. We study the holographic description of this theory and apply the results to the thermodynamics of the rotating black hole from a two dimensional point of view. This setup challenges notions of universality that have been advanced based on simpler models: we find that the mass gap of Kerr-AdS5 corresponds to an undetermined effective coupling in the nAdS2/nCFT1 theory which depends on ultraviolet data.

Thermodynamics of regular black hole

We investigate thermodynamics for a magnetically charged regular black hole (MCRBH), which comes from the action of general relativity and nonlinear electromagnetics, comparing with the Reissner–Norstrom (RN) black hole in both four and two dimensions after dimensional reduction. We find that there is no thermodynamic difference between the regular and RN black holes for a fixed charge Q in both dimensions. This means that the condition for either singularity or regularity at the origin of coordinate does not affect the thermodynamics of black hole. Furthermore, we describe the near-horizon AdS2 thermodynamics of the MCRBH with the connection of the Jackiw–Teitelboim theory. We also identify the near-horizon entropy as the statistical entropy by using the AdS2/CFT1 correspondence.

Gravitational geons in (1+1) dimensions

It is well known that general relativity does not admit gravitational geons that are stationary, asymptotically flat, singularity free and topologically trivial. However, it is likely that general relativity will receive corrections at large curvatures and the modified field equations may admit solutions corresponding to this type of geon. If geons are produced in the early universe and survive until today they could account for some of the dark matter that has been ‘observed’ in galaxies and galactic clusters. In this paper I consider gravitational geons in (1+1)-dimensional theories of gravity. I show that the Jackiw–Teitelboim theory with corrections proportional to R2 and admits gravitational geons. I also show that gravitational geons exist in a class of theories that includes Lagrangians proportional to R2/3.

THERMODYNAMIC DUALITY BETWEEN RN BLACK HOLE AND 2D DILATON GRAVITY

All thermodynamic quantities of the Reissner–Nordström (RN) black hole can be obtained from the dilaton and its potential of two-dimensional (2D) dilaton gravity. The dual relations of four thermodynamic laws are also established. Furthermore, the near-horizon thermodynamics of the extremal RN black hole is completely described by the Jackiw–Teitelboim theory which is obtained by perturbing around the AdS2-horizon.

Quantum-corrected Cardy entropy for generic (1 + 1)-dimensional gravity

Various studies have explored the possibility of explaining the Bekenstein–Hawking (black hole) entropy by way of some suitable state-counting procedure. Notably, many of these treatments have used the well-known Cardy formula as an intermediate step. Our current interest is a recent calculation in which Carlip has deduced the leading-order quantum correction to the (otherwise) classical Cardy formula. In this paper, we apply Carlip's formulation to the case of a generic model of two-dimensional gravity with coupling to a dilaton field. We find that the corrected Cardy entropy includes the anticipated logarithmic ‘area’ term. Such a term is also evident when the entropic correction is derived independently by thermodynamic means. However, there is an apparent discrepancy between the two calculations with regard to the factor in front of the logarithm. In fact, the two values of this prefactor can only agree for very specific two-dimensional models, such as that describing Jackiw–Teitelboim theory.

Integrable models, degenerate horizons and AdS 2 black holes

The near extremal Reissner-Nordström black holes in arbitrary dimensions can be modeled by the Jackiw-Teitelboim (JT) theory. The asymptotic Virasoro symmetry of the corresponding JT model exactly reproduces, via Cardy's formula, the deviation of the Bekenstein-Hawking entropy of the Reissner-Nordström black holes from extremality. We also comment how can we extend this approach to investigate the evaporation process.

P-BRANES, POISSON-SIGMA MODELS AND EMBEDDING APPROACH TO (p+1)-DIMENSIONAL GRAVITY

A generalization of the embedding approach for d-dimensional gravity based upon p-brane theories is proposed. We prove that the D-dimensional p-brane coupled to an antisymmetric tensor field of rank (p+1) provides the dynamical basis for the description of d=(p+1)-dimensional gravity in the isometric embedding formalism. By that we mean that the equations of motion following from this action describe any (p+1)-dimensional space–time (at least locally) once the antisymmetric tensor field is chosen appropriately. "Physical" matter appears in such an approach as a manifestation of a D-dimensional antisymmetric tensor (generalized Kalb–Ramond) background. For the simplest case, the Lorentz harmonic formulation of the bosonic string in a Kalb–Ramond background and its relation to a first order Einstein–Cartan approach for (d=2)-dimensional gravity is analyzed in some detail. We show that a general Poisson-sigma model structure emerges in this case. For the minimal choice of a free D=3 string an interesting "dual" formulation is found which has the structure of a Jackiw–Teitelboim theory, coupled minimally to a massive scalar field. Our approach is intended to serve as a preparation for the study of d-dimensional supergravity theory, either starting from the generalized action of free supersymmetric (d-1)-branes or D(d-1)-branes, or from the corresponding geometric equations ("rheotropic" conditions).

Entropy of 2D black holes from counting microstates

We present a microscopical derivation of the entropy of the black hole solutions of the Jackiw-Teitelboim theory. We show that the asymptotic symmetry of two-dimensional (2D) Anti-de Sitter space is generated by a central extension of the Virasoro algebra. Using a canonical realization of this symmetry and Cardy's formula we calculate the statistical entropy of 2D black holes, which turns out to agree, up to a factor $\sqrt 2$, with the thermodynamical result.

Solitons and black holes

We explore the relationship between black holes in Jackiw-Teitelboim(JT) dilaton gravity and solitons in sine-Gordon field theory. Our analysis expands on the well known connection between solutions of the sine-Gordon equation and constant curvature metrics. In particular, we show that solutions to the dilaton field equations for a given metric in JT theory also solve the sine-Gordon equation linearized about the corresponding soliton. Since the dilaton generates Killing vectors of the constant curvature metric, it is interesting that it has an analoguous interpretation in terms of symmetries of the soliton solution. We also show that from the B${\ddot a}$cklund transformations relating different soliton solutions, it is possible to construct a flat SL(2,R) connection which forms the basis for the gauge theory formulation of JT dilaton gravity.

Nonsingular four-dimensional black holes and the Jackiw-Teitelboim theory.

A four-dimensional dilaton-gravity action whose spherical reduction to two dimensions leads to the Jackiw-Teitelboim theory is presented. A nonsingular black hole solution of the theory is obtained and its physical interpretation is discussed. The classical and semiclassical properties of the solution and of its 2d counterpart are analysed. The 2d theory is also used to model the evaporation process of the near-extremal 4d black hole. We describe in detail the peculiarities of the black hole solutions, in particular the purely topological nature of the Hawking radiation, in the context of the Jackiw-Teitelboim theory.