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At least 307 records · Page 17

Black hole spectroscopy and AdS 2 holography

We compute the spectrum of extremal nonBPS black holes in four dimensions by studying supergravity on their AdS 2 × S2 near horizon geometry. We find that the spectrum exhibits significant simplifications even though supersymmetry is completely broken. We interpret our results in the framework of nAdS 2 /nCFT 1 correspondence and by comparing with dimensional reduction from AdS 3 /CFT 2 duality. As an additional test we compute quantum corrections to extremal black hole entropy on the nonBPS branch and recover results previously determined using very different methods.

79 ASTRONOMY AND ASTROPHYSICS↗

Electromagnetic duality and D3-brane scattering amplitudes beyond leading order

We use on-shell methods to study the non-supersymmetric and supersymmetric low-energy S-matrix on a probe D3-brane, including both the 1-loop contributions of massless states as well as the effects of higher-derivative operators. Our results include: (1) A derivation of the duality invariance of Born-Infeld electrodynamics as the dimensional oxidation of the group of spatial rotations transverse to a probe M2-brane; this is done using a novel implementation of subtracted on-shell recursion. (2) The first explicit loop-level BCJ double-copy in a non-gravitational model, namely the calculation of the 4-point self-dual amplitude of non-supersymmetric Born-Infeld. (3) From previous results for n-point self-dual 1-loop BI amplitudes and the conjectured dimension-shifting relations in Yang-Mills, we obtain an explicit all-multiplicity, at all orders in E, expression for the 1-loop integrand of the MHV sector of N = 4 DBI. (4) For all n > 4, the explicitly integrated duality-violating 1-loop amplitudes (self-dual and next-to-self-dual in pure BI as well as MHV in N = 4 DBI) are shown to be removable at O(ε 0 ) by adding finite local counterterms; we propose that this may be true more generally at 1-loop order. (5) We find that in non-supersymmetric Born-Infeld, not all finite local counterterms needed to restore electromagnetic duality can be constructed using the double-copy with higher-derivative corrections, suggesting a fundamental tension between electromagnetic duality and color-kinematics duality at loop-level. Finally we comment on oxidation of duality symmetries in supergravity and the parallels it has to the M2-brane to D3-brane oxidation demonstrated in this paper.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Finite N indices and the giant graviton expansion

The superconformal index of N = 4 super-Yang Mills theory with U(N) gauge group can be written as a matrix integral over the gauge group. Recently, Murthy demonstrated that this integral can be reexpressed as a sum of terms corresponding to a giant graviton expansion of the index, and provided an explicit formula for the case of a single giant graviton. Here we give similar explicit formulae for an arbitrary number, m ≥ 1, of giant gravitons. We provide 1/2 and 1/16 BPS index examples up to the order where three giant gravitons contribute and demonstrate that the expansion of the matrix integral differs from the giant graviton expansion computed in the supergravity dual. This shows that the giant graviton expansion is not necessarily unique once two or more giant gravitons start appearing.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Orbit averaging coherent states: holographic three-point functions of AdS giant gravitons

We study correlation functions of two AdS giant gravitons in AdS 5 × S 5 and a BPS supergravity mode using holography. In the gauge theory these are described by BPS correlators of Schur polynomials of fully-symmetric representations and a single trace operator. We find full agreement between the semiclassical gravity and gauge theory computations at large N, for both diagonal and off-diagonal structure constants. Our analysis in $\mathcal{N}$ = 4 SYM provides a simpler derivation to the results in the literature, and it can be readily generalized to operators describing bound states of AdS giant gravitons as well as bubbling geometries.

1/N Expansion↗

Rholography, black holes and Scherk-Schwarz

We present a construction of a class of near-extremal asymptotically flat black hole solutions in four (or five) dimensional gauged supergravity with R-symmetry gaugings obtained from Scherk-Schwarz reductions on a circle. The entropy of these black holes is counted holographically by the well known MSW (or D1/D5) system, with certain twisted boundary conditions labeled by a twist parameter ρ. Here, we find that the corresponding (0, 4) (or (4, 4)) superconformal algebras are exactly those studied by Schwimmer and Seiberg, using a twist on the outer automorphism group. The interplay between R-symmetries, ρ-algebras and holography leads us to name our construction “Rholography”.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Boundary terms and three-point functions: an AdS/CFT puzzle resolved

N=8 superconformal field theories, such as the ABJM theory at Chern-Simons level k = 1 or 2, contain 35 scalar operators O IJ with Δ = 1 in the 35 v representation of SO(8). The 3-point correlation function of these operators is non-vanishing, and indeed can be calculated non-perturbatively in the field theory. But its AdS 4 gravity dual, obtained from gauged N=8 supergravity, has no cubic A 3 couplings in its Lagrangian, where A IJ is the bulk dual of OIJ. So conventional Witten diagrams cannot furnish the field theory result. We show that the extension of bulk supersymmetry to the AdS 4 boundary requires the introduction of a finite A 3 counterterm that does provide a perfect match to the 3-point correlator. Boundary supersymmetry also requires infinite counterterms which agree with the method of holographic renormalization. The generating functional of correlation functions of the Δ = 1 operators is the Legendre transform of the on-shell action, and the supersymmetry properties of this functional play a significant role in our treatment.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

On the planar limit of 3d $$ {\mathrm{T}}_{\rho}^{\sigma}\left[\mathrm{SU}\left(\mathrm{N}\right)\right] $$

A bstract We discuss a limit of 3d $$ {T}_{\rho}^{\sigma}\left[\mathrm{SU}(N)\right] $$ T ρ σ SU N quiver gauge theories in which the number of nodes is large and the ranks scale quadratically with the length of the quiver. The sphere free energies and topologically twisted indices are obtained using supersymmetric localization. Both scale quartically with the length of the quiver and quadratically with N , with trilogarithm functions depending on the quiver data as coefficients. The IR SCFTs have well-behaved supergravity duals in Type IIB, and the free energies match precisely with holographic results. Previously discussed theories with N 2 ln N scaling arise as limiting cases. Each balanced 3d quiver theory is linked to a 5d parent, whose matrix model is related and dominated by the same saddle point, leading to close relations between BPS observables.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

The sub-leading scattering waveform from amplitudes

We compute the next-to-leading order term in the scattering waveform of uncharged black holes in classical general relativity and of half-BPS black holes in $\mathcal{N}$ = 8 supergravity. We propose criteria, generalizing explicit calculations at next-to-leading or der, for determining the terms in amplitudes that contribute to local observables. For general relativity, we construct the relevant classical integrand through generalized unitary in two distinct ways, (1) in a heavy-particle effective theory and (2) in general relativity minimally-coupled to scalar fields. With a suitable prescription for the matter propagator in the former, we find agreement between the two methods, thus demonstrating the absence of interference of quantum and classically-singular contributions. The classical $\mathcal{N}$ = 8 integrand for massive scalar fields is constructed through dimensional reduction of the known five-point one-loop integrand. Our calculation exhibits novel features compared to conservative calculations and inclusive observables, such as the appearance of master integrals with intersecting matter lines and the appearance of a classical infrared divergence whose absence from classical observables requires a suitable definition of the retarded time.

79 ASTRONOMY AND ASTROPHYSICS↗

Universality in logarithmic temperature corrections to near-extremal rotating black hole thermodynamics in various dimensions

The low-temperature thermodynamics of near-extremal rotating black holes has recently been revisited to incorporate one-loop contributions that are dominant in this regime. We discuss these quantum corrections to the gravitational path integral for asymptotically Anti de-Sitter black holes in four and five dimensions. In four dimensions we explicitly consider Kerr-AdS 4 , Kerr-Newman-AdS 4 and the rotating black hole in $\mathcal{N}$ = 4 gauged supergravity with two scalars and two electric charges turned on. In five dimensions we explicitly address the asymptotically flat Myers-Perry black hole and the Kerr-AdS5 black hole. In every case we find that tensor modes contribute $\frac{3}{2}$logT Hawking to the low-temperature thermodynamics. We identify the root cause of this universality in two facts: (i) the universal presence of a SL(2, $\mathbb{R}$) subgroup of isometries in the near-horizon geometry and (ii) a set of cancellations in the Lichnerowicz operator. We show that these two conditions hold for near-extremal black holes in asymptotically flat and asymptotically AdS spacetimes of various dimensions.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

BPS Kerr-AdS time machines

It was recently observed that Kerr-AdS metrics with negative mass can describe smooth spacetimes that have a region within which naked closed time-like curves can arise, bounded by a velocity of light surface. Such spacetimes are sometimes known as time machines. In this paper we study the BPS limit of these metrics, and find that the mass and angular momenta become discretised. The completeness of the spacetime also requires that the asymptotic time coordinate be periodic, with precisely the same period as that which arises naturally for the global AdS, viewed as a hyperboliod in one extra dimension, in which the time machine spacetime is immersed. For the case of equal angular momenta in odd dimensions, we construct the Killing spinors explicitly, and show they are consistent with the global structure. Thus in examples where the solutions can be embedded in gauged supergravity, they will be supersymmetric. As a result, we also compare the global structure of the BPS AdS3 time machine with the BTZ black hole, and show that the global structure allows two different supersymmetric limits.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

String theory of supertubes

String theory on AdS 3 backgrounds arises as an IR limit of Little String Theory on NS 5 -branes. A wide variety of holographic RG flows from the fivebrane theory in the UV to (orbifolds of) AdS 3 in the IR is amenable to exact treatment in worldsheet string theory as a class of null-gauged WZW models. The condensate of stringy winding operators which resolves the near-source structure of fivebranes on the Coulomb branch plays a crucial role in AdS 3 , revealing stringy structure invisible to the supergravity approximation. As a result, the D-brane sector contains precursors of the long strings which dominate black hole entropy in the dual spacetime CFT.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Quantum corrections to central charges and supersymmetric Casimir energy in AdS 3 /CFT 2

We study the Casimir energy of bulk fields in AdS 3 and its relation to subleading terms in the central charge of the dual CFT 2 . Computing both sides of the standard CFT 2 relation E = - c /12 independently we show that this relation is not necessarily satisfied at the level of individual bulk supergravity states, but in theories with sufficient supersymmetry it is restored at the level of bulk supermultiplets. Assuming only (0, 2) supersymmetry (or more), we improve the situation by relating quantum corrections to the central charge and the supersymmetric Casimir energy which in turn is related to an index. These relations adapt recent progress on the AdS 5 /CFT 4 correspondence to AdS 3 /CFT 2 holography. We test our formula successfully in several examples, including the (0, 4) MSW theory describing classes of 4D black holes and the large (4, 4) theory that is interesting for higher spin holography. We also make predictions for the subleading central charges in several recently proposed (2, 2) dualities where the CFT 2 is not yet well-understood.

1/N Expansion↗

The role of singletons in S7 compactifications

We derive the isometry irrep content of squashed seven-sphere compactifications of eleven-dimensional supergravity, i.e., the left-squashed (LS7) with N = 1 and right-squashed (RS7) with N = 0 supersymmetry, in a manner completely independent of the round sphere. Then we compare this result with the spectrum obtained by Higgsing the round sphere spectrum. This way we discover features of the spectra which makes it possible to argue that the only way the round spectrum can be related by a Higgs mechanism to the one of LS7 is if the singletons are included in the round sphere spectrum. For this to work also in the RS7 case it seems that the gravitino of the LS7 spectrum must be replaced by a fermionic singleton present in the RS7 spectrum.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Nonrenormalization theorem for $\mathcal{N}$ = (4, 4) interface entropy

We derive a formula for the half-BPS interface entropy between any pair of $\mathcal{N}$ = (4, 4) theories on the same conformal manifold. This generalizes the diastasis formula derived in [1] for $\mathcal{N}$ = (2, 2) theories, which is restricted to the conformal submanifolds generated by either chiral or twisted chiral multiples of $\mathcal{N}$ = (2, 2) supersymmetry. To derive the $\mathcal{N}$ = (4, 4) formula, we use the fact that the conformal manifold of $\mathcal{N}$ = (4, 4) theories is symmetric and quaternionic-Kähler and that its isotropy group contains the SU(2) ⊗ SU(2) external automorphism of the $\mathcal{N}$ = (4, 4) superconformal algebra. As an application of the formula, we prove a supersymmetric non-renormalization theorem, which explains the observation in [2] that the interface entropy for half-BPS Janus solutions in type IIB supergravity on AdS 3 × S 3 × T 4 coincides with the corresponding quantity in their free conformal field limits.

AdS-CFT correspondence↗

Supergravitational conformal Galileons

The worldvolume actions of 3+1 dimensional bosonic branes embedded in a five-dimensional bulk space can lead to important effective field theories, such as the DBI conformal Galileons, and may, when the Null Energy Condition is violated, play an essential role in cosmological theories of the early universe. These include Galileon Genesis and “bouncing” cosmology, where a pre-Big Bang contracting phase bounces smoothly to the presently observed expanding universe. Perhaps the most natural arena for such branes to arise is within the context of superstring and M -theory vacua. Here, not only are branes required for the consistency of the theory, but, in many cases, the exact spectrum of particle physics occurs at low energy. However, such theories have the additional constraint that they must be N = 1 supersymmetric. This motivates us to compute the worldvolume actions of N = 1 supersymmetric three-branes, first in flat superspace and then to generalize them to N = 1 supergravitation. In this paper, for simplicity, we begin the process, not within the context of a superstring vacuum but, rather, for the conformal Galileons arising on a co-dimension one brane embedded in a maximally symmetric AdS 5 bulk space. We proceed to N = 1 supersymmetrize the associated worldvolume theory and then generalize the results to N = 1 supergravity, opening the door to possible new cosmological scenarios

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

4d SCFTs from negative-degree line bundles

We compose 4d $\mathcal{N}$ =1 quantum field theories by compactifying the (2,0) theories on a Riemann surface with genus g and n punctures, where the normal bundle decomposes into a sum of two line bundles with possibly negative degrees p and q . Not long ago, the only available field-theoretic constructions required the line bundle degrees to be nonnegative, although supergravity solutions were constructed in the literature for the zero-puncture case for all p and q . Here, we provide field-theoretic constructions and computations of the central charges of 4d $\mathcal{N}$=1 SCFTs that are the IR limit of M5-branes wrapping a surface with general p or q negative, for general genus g and number of maximal punctures n .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Notes on the D = 11 pure spinor superparticle

The D = 11 pure spinor superparticle has been shown to describe linearized D = 11supergravityinamanifestlycovariantway. Anumberofauthorshaveproposedthat its correlation functions be used to compute amplitudes. The use of the scalar structure of the eleven-dimensional pure spinor top cohomology introduces a natural measure for computing such correlation functions. This prescription requires the construction of ghost number one and zero vertex operators. In these notes, we construct explicitly a ghost number one vertex operator but show the incompatibiliy of a ghost number zero vertex operator satisfying a standard descent equation for D = 11 supergravity.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

$T\overline{T}$ deformations of supersymmetric quantum mechanics

We define a manifestly supersymmetric version of the $T\overline{T}$ deformation appropriate for a class of (0 + 1)-dimensional theories with $\mathcal{N}$ = 1 or $\mathcal{N}$ = 2 supersymmetry, including one presentation of the super-Schwarzian theory which is dual to JT supergravity. These deformations are written in terms of Noether currents associated with translations in superspace, so we refer to them collectively as f($\mathcal{Q}$) deformations. We provide evidence that the f($\mathcal{Q}$) deformations of $\mathcal{N}$ = 1 and $\mathcal{N}$ = 2 theories are on-shell equivalent to the dimensionally reduced supercurrent-squared deformations of 2d theories with $\mathcal{N}$ = (0, 1) and $\mathcal{N}$ = (1, 1)supersymmetry, respectively. In the $\mathcal{N}$ = 1 case, we present two forms of the f($\mathcal{Q}$) deformation which drive the same flow, and clarify their equivalence by studying the analogous equivalent deformations in the non-supersymmetric setting.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗