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Giveon, Amit

Publications and source records attributed to Giveon, Amit.

16 records
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DOE OSTI2024

Thermal partition function of $$ {J}_3{\overline{J}}_3 $$ deformed AdS3

Abstract We derive a compact formula for the one-loop, bosonic string partition function of Euclideanized$$ {J}_3{\overline{J}}_3 $$ J 3 J ¯ 3 deformedAdS 3 with periodic Euclidean time as an integral transform of the partition function of the undeformed EuclideanizedAdS 3 . Such a deformation is interpretable as an irrelevant “single-trace$$ T\overline{T} $$ T T ¯ deformation” of the boundary. We will do this by first establishing a formal procedure to compute a worldsheet torus zero point function for an exactly marginal$$ J\overline{J} $$ J J ¯ deformation of a sigma model with U(1) L × U(1) R global symmetry. We then describe how this procedure is implemented on SL(2,R) sigma model and its Euclidean continuation. Finally, we describe the embedding of the deformed SL(2,R) torus amplitude into critical string theory and interpret the result as the leading perturbative contribution to the thermal partition function of the deformed theory.

Physics↗
DOE OSTI2024

On string theory on deformed BTZ and $$ \textrm{T}\overline{\textrm{T}} $$

Abstract Aspects of superstring theory on deformed BTZ black holes, formed nearkNS5 branes bypfundamental strings, and single-trace$$ T\overline{T} $$ T T ¯ holography, are presented. The excitation energy of a singly wound long string plus its contribution to the energy of the black hole, 1/pfraction of the black-hole energy, is the same as that in$$ T\overline{T} $$ T T ¯ deformed CFT 2 withc= 6k. This supports the claim that the black hole can be thought of as a state in a symmetric product ofpCFT 2 ’s of central charge 6k, where the black-hole energy is split equally among allpfactors. A comment on superstring theory on deformed global AdS 3 is also presented.

Physics↗
DOE OSTI2023

Momentum in single-trace $T$$\overline{T}$ holography

We continue our exploration of the holographic duality between string theory in backgrounds that interpolate between asymptotically linear dilaton spacetime in the UV and AdS 3 in the IR, and the corresponding boundary theories. In previous papers, [1], [2], we showed that states in the bulk theory that are described by non-trivial asymptotically linear dilaton geometries, such as black holes and deformed global AdS 3 , can be described in the boundary theory by a single-trace $T$$\overline{T}$ deformation of a symmetric product theory. In those papers, we restricted to states with vanishing (angular) momentum; in this paper, we extend the analysis to states with arbitrary momentum, and show that the picture presented in the earlier papers generalizes to this case.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Asymptotically Free AdS 3 /CFT 2

We propose a new AdS 3 /CFT 2 duality, in which the bulk string theory has a target spacetime AdS 3 times a squashed three-sphere $S$$^{3}_{b}$, and the dual CFT 2 is a symmetric product of sigma models on R Φ × $S$$^{3}_{b}$, deformed by a Φ-dependent Z 2 twist operator. The duality maps the asymptotic region of AdS 3 to the region Φ → ∞, where the twist interaction in the CFT 2 turns off. The AdS 3 backgrounds in question have R AdS < ℓ s , and so lie on the string side of the string/black hole correspondence transition. As a consequence, the high energy density of states consists of a string gas in AdS 3 rather than an ensemble of BTZ black holes. Furthermore, this property allows us to derive the dual CFT 2 by a systematic analysis of the worldsheet string theory on AdS 3 .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Strings in irrelevant deformations of AdS 3 /CFT 2

We generalize our recent analysis [1] of probe string dynamics to the case of general single-trace TT¯,JT¯ and TJ¯ deformations. We show that in regions in coupling space where the bulk geometry is smooth, the classical trajectories of such strings are smooth and approach the linear dilaton boundary at either the far past or the far future. These trajectories give rise to quantum scattering states with arbitrarily high energies. When the bulk geometry has closed timelike curves (CTC’s), the trajectories are singular for energies above a critical value E c . This singularity occurs in the region with CTC’s, and the value of E c agrees with that read off from the dual boundary theory for all values of the couplings and charges.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Comments on D3-brane holography

We revisit the idea that the quantum dynamics of open strings ending on N D3-branes in the large N limit can be described at large ‘t Hooft coupling by classical closed string theory in the background created by the D3-branes in asymptotically flat spacetime. We study the resulting thermodynamics and compute the Hagedorn temperature and other properties of the D3-brane worldvolume theory in this regime. We also consider the theory in which the D3-branes are replaced by negative branes and show that its thermodynamics is well behaved. We comment on the idea that this theory can be thought of as an irrelevant deformation of $ \mathcal{N} $ = 4 SYM, and on its relation to $ T\overline{T} $ deformed CFT 2 .

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

$T\overline{T}$, black holes and negative strings

String theory on AdS 3 has a solvable single-trace irrelevant deformation that is closely related to $T\overline{T}$. For one sign of the coupling, it leads to an asymptotically linear dilaton spacetime, and a corresponding Hagedorn spectrum. For the other, the resulting spacetime has a curvature singularity at a finite radial location, and an upper bound on the energies of states. Beyond the singularity, the signature of spacetime is flipped and there is an asymptotically linear dilaton boundary at infinity. We study the properties of black holes and fundamental strings in this spacetime, and find a sensible picture. The singularity does not give rise to a hard ultraviolet wall for excitations -one must include the region beyond it to understand the theory. The size of black holes diverges as their energy approaches the upper bound, as does the location of the singularity. Fundamental strings pass smoothly through the singularity, but if their energy is above the upper bound, their trajectories are singular. From the point of view of the boundary at infinity, this background can be thought of as a vacuum of Little String Theory which contains a large number of negative strings.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

$\boldsymbol {T\overline{T}}$ , $\boldsymbol {J\overline{T}}$ , $\boldsymbol{T\overline{J}}$ and string theory

We calculate the spectrum of a two dimensional CFT on a cylinder, perturbed by a generallinear combination of ${T\overline{T}}$,$ {J\overline{T}}$ and ${T\overline{J}}$, by utilizing the relation of this problem to certainsolvable single trace current-current deformations of theworldsheet theory of strings on AdS 3 . We show that this spectrum is well behaved (i.e.the energies are real) if and onlyif the dual bulk geometry is well behaved (i.e.the signature of the bulk spacetime is (1,2)and there are no closed timelike curves). Here, we also comment on the relations of string theory on AdS 3 and its deformations to symmetric product CFT’s, matrix string theory, and a black hole description of highly excited fundamental strings.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Modular covariance and uniqueness of $ J\overline{T}$ deformed CFTs

We study families of two dimensional quantum field theories, labeled by a dimensionful parameter μ, that contain a holomorphic conserved U(1) current J(z). We assume that these theories can be consistently defined on a torus, so their partition sum, with a chemical potential for the charge that couples to J, is modular covariant. We further require that in these theories, the energy of a state at finite μ is a function only of μ, and of the energy, momentum and charge of the corresponding state at μ = 0, where the theory becomes conformal. We show that under these conditions, the torus partition sum of the theory at μ = 0 uniquely determines the partition sum (and thus the spectrum) of the perturbed theory, to all orders in μ, to be that of a $μJ\bar{T}$ deformed conformal field theory (CFT). We derive a flow equation for the $J\bar{T}$ deformed partition sum, and use it to study non-perturbative effects. We find non-perturbative ambiguities for any non-zero value of μ, and comment on their possible relations to holography.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2019

Modular invariance and uniqueness of $T\overline{T} $ deformed CFT

Any two dimensional quantum field theory that can be consistently defined on a torus is invariant under modular transformations. In this paper we study families of quantum field theories labeled by a dimensionful parameter t, that have the additional property that the energy of a state at finite t is a function only of t and of the energy and momentum of the corresponding state at t = 0, where the theory becomes conformal. We show that under this requirement, the partition sum of the theory at t = 0 uniquely determines the partition sum (and thus the spectrum) of the perturbed theory, to all orders in t, to be that of a $T\bar{T}$ deformed CFT. Non-perturbatively, we find that for one sign of t (for which the energies are real) the partition sum is uniquely determined, while for the other sign we find non-perturbative ambiguities. We characterize these ambiguities and comment on their possible relations to holography.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

$J\overline{T}$ deformed CFT 2 and string theory

We study two dimensional conformal field theory with a left-moving conserved current J, perturbed by an irrelevant, Lorentz symmetry breaking operator with the quantum numbers of J$\overline{T}$ , using a combination of field and string theoretic techniques. We show that the spectrum of the theory has some interesting features, which may shed light on systems of interest for holography and black hole physics. $\overline{T}$

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

A solvable irrelevant deformation of AdS 3 /CFT 2

Recently we proposed a universal solvable irrelevant deformation of AdS 3 /CFT 2 duality, which leads in the ultraviolet to a theory with a Hagedorn entropy [1]. In this note we provide a worldsheet description of this theory as a coset CFT, and compare its spectrum to the field theory predictions of [2, 3].

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

TT̄ and LST

It was recently shown that the theory obtained by deforming a general two dimensional conformal theory by the irrelevant operator $T\bar{T}$ is solvable. In the context of holography, a large class of such theories can be obtained by studying string theory on AdS 3 . We show that a certain single trace $T\bar{T}$ deformation of the boundary CFT 2 gives rise in the bulk to string theory in a background that interpolates between AdS 3 in the IR and a linear dilaton spacetime in the UV, i.e. to a two dimensional vacuum of Little String Theory. This construction provides holographic duals for a large class of vacua of string theory in asymptotically linear dilaton spacetimes, and sheds light on the UV behavior of $T\bar{T}$ deformed CFT 2 . It may provide a step towards holography in flat spacetime.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2016

Stringy horizons II

We show that the spectrum of normalizable states on a Euclidean SL(2, R)/U(1) black hole exhibits a duality between oscillator states and wound strings. This duality generalizes the identification between a normalizable mode of dilaton gravity on the cigar and a mode of the tachyon with winding number one around the Euclidean time circle, which plays an important role in the FZZ correspondence. It implies that normalizable states on a large Euclidean black hole have support at widely separated scales. In particular, localized states that are extended over the cap of the cigar (the Euclidian analog of the black hole atmosphere) have a component that is localized near the tip of the cigar (the analog of the stretched horizon). As a consequence of this duality, the states exhibit a transition as a function of radial excitation level. From the perspective of a low energy probe, low lying states are naturally thought of as oscillator states in the black hole atmosphere, while at large excitation level they are naturally described as wound strings. As the excitation level increases, the size of the states first decreases and then increases. This behavior is expected to be a general feature of black hole horizons in string theory.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗