Soumangsu Chakraborty
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Soumangsu Chakraborty has a total of 28 co-authors. Here are the top co-authors by number of shared publications:
- Amit Giveon
Racah Institute of Physics The Hebrew University 91904 Jerusalem Israel
10 shared publications - Akikazu Hashimoto
Department of Physics University of Wisconsin Madison 53706 WI USA
7 shared publications - David Kutasov
University of Chicago
5 shared publications - Gela Patashuri
The Ohio State University
3 shared publications - Mikhail Goykhman
William I. Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, USA
3 shared publications - Amit Giveon
The Hebrew University
2 shared publications
Latest Publications
- Open Access
- 22 July 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (7)
Generating rotation in a snap
A bstract: We build a technique to generate rotation from arbitrary static solutions that asymptote to four- or five-dimensional Minkowski spacetime based on Clément’s approach [ Phys. Rev. D 57 (1998) 4885]. The method is purely algebraic and does not require solving Einstein equations. It proceeds by transforming the static solution to AdS×S asymptotics, performing a coordinate shift to a uniformly rotating frame, and then transforming the solution back to asymptotically flat spacetime. We implement this construction in five-dimensional minimal supergravity, although it applies more broadly to any framework admitting AdS×S geometries and relevant sigma-model transformations. As a first application, we recover simply the Kerr and Myers-Perry black holes directly from Schwarzschild black holes. We then apply the method to the linear class of static Weyl solutions and obtain the first linear ansatz describing an arbitrary number of non-extremal rotating and charged sources. This approach provides a systematic and simple route to constructing non-extremal rotating geometries in four and five dimensions.
- 22 July 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (7)
Open AccessGenerating rotation in a snap
A bstract: We build a technique to generate rotation from arbitrary static solutions that asymptote to four- or five-dimensional Minkowski spacetime based on Clément’s approach [ Phys. Rev. D 57 (1998) 4885]. The method is purely algebraic and does not require solving Einstein equations. It proceeds by transforming the static solution to AdS×S asymptotics, performing a coordinate shift to a uniformly rotating frame, and then transforming the solution back to asymptotically flat spacetime. We implement this construction in five-dimensional minimal supergravity, although it applies more broadly to any framework admitting AdS×S geometries and relevant sigma-model transformations. As a first application, we recover simply the Kerr and Myers-Perry black holes directly from Schwarzschild black holes. We then apply the method to the linear class of static Weyl solutions and obtain the first linear ansatz describing an arbitrary number of non-extremal rotating and charged sources. This approach provides a systematic and simple route to constructing non-extremal rotating geometries in four and five dimensions.
- Open Access
- 21 November 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (11) , 128
Extremal curves in single-trace $T\overline{T }$-holographyA bstract: In this paper, we continue the study of single-trace $$T\overline{T }$$ -holography where the boundary field theory can be realized as a CFT 2 deformed by a single-trace irrelevant operator of dimension (2 , 2) and dual spacetime geometry is AdS 3 smoothly glued to flat spacetime with a linear dilaton near the boundary. In this non-AdS holographic framework, we propose that the length of real extremal curves connecting the two boundaries of an eternal black hole at fixed boundary time captures the time-evolved entanglement entropy of an entangled, quenched boundary system. At late times, we find two analytic extremal solutions in the complexified geometry, which become real in complementary temperature regimes. Focusing only on the real solutions leads to a non-analyticity at a critical temperature T c , which we interpret as a second-order phase transition separating a local (CFT 2 ) phase from a non-local (Little String Theory) phase.- 21 November 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (11) , 128
Open AccessExtremal curves in single-trace $T\overline{T }$-holographyA bstract: In this paper, we continue the study of single-trace $$T\overline{T }$$ -holography where the boundary field theory can be realized as a CFT 2 deformed by a single-trace irrelevant operator of dimension (2 , 2) and dual spacetime geometry is AdS 3 smoothly glued to flat spacetime with a linear dilaton near the boundary. In this non-AdS holographic framework, we propose that the length of real extremal curves connecting the two boundaries of an eternal black hole at fixed boundary time captures the time-evolved entanglement entropy of an entangled, quenched boundary system. At late times, we find two analytic extremal solutions in the complexified geometry, which become real in complementary temperature regimes. Focusing only on the real solutions leads to a non-analyticity at a critical temperature T c , which we interpret as a second-order phase transition separating a local (CFT 2 ) phase from a non-local (Little String Theory) phase. - Open Access
- 16 October 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (10) , 1-23
On string theory on (deformed) $Ad{S}_{3}\times {\mathbb{T}}^{3}$A bstract: We revisit the fermionic string theory on $$Ad{S}_{3}\times \mathcal{N}$$ with k = 1, and its single-trace $$T\overline{T }$$ deformation, with a focus on the (2, 2) superstring on (deformed) $$Ad{S}_{3}\times {\mathbb{T}}^{3}$$ . In a certain limit, it is dual to the symmetric product of the ( $$T\overline{T }$$ -deformed) SCFT 2 on $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ . We present the winding-one delta-function normalizable worldsheet operators which, in the k = 1 decoupling limit, correspond to those of $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ in spacetime. We then demonstrate how their properties in string theory reproduce those of $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ , or more generally, of a ( $$T\overline{T }$$ -deformed) $${\mathbb{R}}\times \mathcal{N}$$ seed of the boundary theory.- 16 October 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (10) , 1-23
Open AccessOn string theory on (deformed) $Ad{S}_{3}\times {\mathbb{T}}^{3}$A bstract: We revisit the fermionic string theory on $$Ad{S}_{3}\times \mathcal{N}$$ with k = 1, and its single-trace $$T\overline{T }$$ deformation, with a focus on the (2, 2) superstring on (deformed) $$Ad{S}_{3}\times {\mathbb{T}}^{3}$$ . In a certain limit, it is dual to the symmetric product of the ( $$T\overline{T }$$ -deformed) SCFT 2 on $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ . We present the winding-one delta-function normalizable worldsheet operators which, in the k = 1 decoupling limit, correspond to those of $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ in spacetime. We then demonstrate how their properties in string theory reproduce those of $${\mathbb{R}}\times {\mathbb{T}}^{3}$$ , or more generally, of a ( $$T\overline{T }$$ -deformed) $${\mathbb{R}}\times \mathcal{N}$$ seed of the boundary theory. - Open Access
Extremal curves in single-trace $T\bar{T}$-holography
In this paper, we continue the study of single-trace $T\bar{T}$-holography where the boundary field theory can be realized as a CFT$_2$ deformed by a single-trace irrelevant operator of dimension $(2,2)$ and dual spacetime geometry is $AdS_3$ smoothly glued to flat spacetime with a linear dilaton near the boundary. In this non-AdS holographic framework, we propose that the length of real extremal curves connecting the two boundaries of an eternal black hole at fixed boundary time captures the time-evolved entanglement entropy of an entangled, quenched boundary system. At late times, we find two analytic extremal solutions in the complexified geometry, which become real in complementary temperature regimes. Focusing only on the real solutions leads to a non-analyticity at a critical temperature $T_c$, which we interpret as a second-order phase transition separating a local (CFT$_2$) phase from a non-local (Little String Theory) phase.Open AccessExtremal curves in single-trace $T\bar{T}$-holography
In this paper, we continue the study of single-trace $T\bar{T}$-holography where the boundary field theory can be realized as a CFT$_2$ deformed by a single-trace irrelevant operator of dimension $(2,2)$ and dual spacetime geometry is $AdS_3$ smoothly glued to flat spacetime with a linear dilaton near the boundary. In this non-AdS holographic framework, we propose that the length of real extremal curves connecting the two boundaries of an eternal black hole at fixed boundary time captures the time-evolved entanglement entropy of an entangled, quenched boundary system. At late times, we find two analytic extremal solutions in the complexified geometry, which become real in complementary temperature regimes. Focusing only on the real solutions leads to a non-analyticity at a critical temperature $T_c$, which we interpret as a second-order phase transition separating a local (CFT$_2$) phase from a non-local (Little String Theory) phase. - Open AccessOn string theory on (deformed) $AdS_3\times \mathbb{T}^3$We revisit the fermionic string theory on $AdS_3\times \mathcal{N}$ with $k=1$, and its single-trace $T\bar T$ deformation, with a focus on the $(2,2)$ superstring on (deformed) $AdS_3\times \mathbb{T}^3$. In a certain limit, it is dual to the symmetric product of the ($T\bar T$-deformed) SCFT$_2$ on $\mathbb{R}\times \mathbb{T}^3$. We present the winding-one delta-function normalizable worldsheet operators which, in the $k=1$ decoupling limit, correspond to those of $\mathbb{R}\times \mathbb{T}^3$ in spacetime. We then demonstrate how their properties in string theory reproduce those of $\mathbb{R}\times\mathbb{T}^3$, or more generally, of a ($T\bar{T}$-deformed) $\mathbb{R}\times\mathcal{N}$ seed of the boundary theory.Open AccessOn string theory on (deformed) $AdS_3\times \mathbb{T}^3$We revisit the fermionic string theory on $AdS_3\times \mathcal{N}$ with $k=1$, and its single-trace $T\bar T$ deformation, with a focus on the $(2,2)$ superstring on (deformed) $AdS_3\times \mathbb{T}^3$. In a certain limit, it is dual to the symmetric product of the ($T\bar T$-deformed) SCFT$_2$ on $\mathbb{R}\times \mathbb{T}^3$. We present the winding-one delta-function normalizable worldsheet operators which, in the $k=1$ decoupling limit, correspond to those of $\mathbb{R}\times \mathbb{T}^3$ in spacetime. We then demonstrate how their properties in string theory reproduce those of $\mathbb{R}\times\mathbb{T}^3$, or more generally, of a ($T\bar{T}$-deformed) $\mathbb{R}\times\mathcal{N}$ seed of the boundary theory.
- Open Access
- 10 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-25
The M2-M5 Mohawk
A bstract: We show that the near-brane back-reaction of M2 branes ending on M5 branes has a rich “spike structure” that is determined by partitioning the numbers of M2 branes that are terminating on groups of M5 branes. The near-brane limit of the metric describing these branes has an AdS 3 factor, implying the existence of a dual CFT. Each partition of the M2 and M5 charges among spikes gives rise to a different “mohawk” revealing a new layer of brane fractionation. We conjecture that all these mohawks are dual to ground states of near-brane-intersection CFT’s. We show that the supergravity solutions describing these mohawks are part of the large families of AdS 3 × S 3 × S 3 solutions described in [1]. We identify precisely which of these families are relevant to brane intersections and show that the AdS 3 invariance emerges from the self-similarity of the spikes.
- 10 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-25
Open AccessThe M2-M5 Mohawk
A bstract: We show that the near-brane back-reaction of M2 branes ending on M5 branes has a rich “spike structure” that is determined by partitioning the numbers of M2 branes that are terminating on groups of M5 branes. The near-brane limit of the metric describing these branes has an AdS 3 factor, implying the existence of a dual CFT. Each partition of the M2 and M5 charges among spikes gives rise to a different “mohawk” revealing a new layer of brane fractionation. We conjecture that all these mohawks are dual to ground states of near-brane-intersection CFT’s. We show that the supergravity solutions describing these mohawks are part of the large families of AdS 3 × S 3 × S 3 solutions described in [1]. We identify precisely which of these families are relevant to brane intersections and show that the AdS 3 invariance emerges from the self-similarity of the spikes.
- Open Access
- 8 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-40
Microstates of non-extremal black holes: a new hope
A bstract: We provide a new roadmap for constructing microstates of non-extremal black holes in supergravity. First, we review the non-linear sigma model of five-dimensional supergravity governing stationary solutions with a U(1) isometry and present the first generalized Ernst formulation of this model. We then revisit solution-generating techniques associated to the coset model symmetry, Ernst formalism and inverse scattering method. While some of these techniques have been extensively used to generate non-extremal black holes and black rings in supergravity, we demonstrate how they can be adapted to construct systematically non-BPS smooth horizonless geometries that have the same mass and charges as non-extremal black holes. To illustrate these methods, we construct novel static solutions of this type, including a non-BPS generalization of the $$ \frac{1}{2} $$ -BPS Gibbons-Hawking center, which has served as the fundamental building block of multicenter microstates of BPS black holes.- 8 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-40
Open AccessMicrostates of non-extremal black holes: a new hope
A bstract: We provide a new roadmap for constructing microstates of non-extremal black holes in supergravity. First, we review the non-linear sigma model of five-dimensional supergravity governing stationary solutions with a U(1) isometry and present the first generalized Ernst formulation of this model. We then revisit solution-generating techniques associated to the coset model symmetry, Ernst formalism and inverse scattering method. While some of these techniques have been extensively used to generate non-extremal black holes and black rings in supergravity, we demonstrate how they can be adapted to construct systematically non-BPS smooth horizonless geometries that have the same mass and charges as non-extremal black holes. To illustrate these methods, we construct novel static solutions of this type, including a non-BPS generalization of the $$ \frac{1}{2} $$ -BPS Gibbons-Hawking center, which has served as the fundamental building block of multicenter microstates of BPS black holes. - Open Access
- 5 March 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (3) , 1-16
Effective AdS3/CFT2
In [1], it was pointed out that superstring theory on AdS 3 with (NS, NS) B-field background and R AdS/l s = $$ \sqrt{k} $$ < 1 is dual to a symmetric product CFT deformed by an operator in the ℤ 2 twisted sector. We generalize the analysis of [1] to k > 1, and show that the resulting picture matches that discussed in the bosonic case in [2]. We argue that in the critical case, k = 1 [3], the ℤ 2 twisted deformation remains non-trivial. This resolves some confusions in the literature.- 5 March 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (3) , 1-16
Open AccessEffective AdS3/CFT2
In [1], it was pointed out that superstring theory on AdS 3 with (NS, NS) B-field background and R AdS/l s = $$ \sqrt{k} $$ < 1 is dual to a symmetric product CFT deformed by an operator in the ℤ 2 twisted sector. We generalize the analysis of [1] to k > 1, and show that the resulting picture matches that discussed in the bosonic case in [2]. We argue that in the critical case, k = 1 [3], the ℤ 2 twisted deformation remains non-trivial. This resolves some confusions in the literature. - Open Access
- 19 December 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (12) , 1-22
Path integral of free fields and the determinant of Laplacian in warped space-time
A bstract: We revisit the problem of computing the determinant of Klein-Gordon operator ∆ = −∇ 2 + M 2 on Euclideanized AdS 3 with the Euclideanized time coordinate compactified with period β , H 3 / Z , by explicitly computing its eigenvalues and computing their product. Upon assuming that eigenfunctions are normalizable on H 3 / Z , we found that there are no such eigenfunctions. Upon closer examination, we discover that the intuition that H 3 / Z is like a box with normalizable eigenfunctions was false, and that there is, instead, a set of eigenfunctions which forms a continuum. Somewhat to our surprise, we find that there is a different operator $$ \overset{\sim }{\Delta } $$ = r 2 ∆, which has the property that (1) the determinant of ∆ and the determinant of r 2 ∆ have the same dependence on β , and that (2) the Green’s function of ∆ can be spectrally decomposed into eigenfunctions of $$ \overset{\sim }{\Delta } $$ . We identify the $$ \overset{\sim }{\Delta } $$ operator as the “weighted Laplacian” in the context of warped compactifications, and comment on possible applications.- 19 December 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (12) , 1-22
Open AccessPath integral of free fields and the determinant of Laplacian in warped space-time
A bstract: We revisit the problem of computing the determinant of Klein-Gordon operator ∆ = −∇ 2 + M 2 on Euclideanized AdS 3 with the Euclideanized time coordinate compactified with period β , H 3 / Z , by explicitly computing its eigenvalues and computing their product. Upon assuming that eigenfunctions are normalizable on H 3 / Z , we found that there are no such eigenfunctions. Upon closer examination, we discover that the intuition that H 3 / Z is like a box with normalizable eigenfunctions was false, and that there is, instead, a set of eigenfunctions which forms a continuum. Somewhat to our surprise, we find that there is a different operator $$ \overset{\sim }{\Delta } $$ = r 2 ∆, which has the property that (1) the determinant of ∆ and the determinant of r 2 ∆ have the same dependence on β , and that (2) the Green’s function of ∆ can be spectrally decomposed into eigenfunctions of $$ \overset{\sim }{\Delta } $$ . We identify the $$ \overset{\sim }{\Delta } $$ operator as the “weighted Laplacian” in the context of warped compactifications, and comment on possible applications. - Open Access
- 16 July 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (7) , 1-46
Thermal partition function of $ {J}_3{\overline{J}}_3 $ deformed AdS3We derive a compact formula for the one-loop, bosonic string partition function of Euclideanized $$ {J}_3{\overline{J}}_3 $$ deformed AdS 3 with periodic Euclidean time as an integral transform of the partition function of the undeformed Euclideanized AdS 3. Such a deformation is interpretable as an irrelevant “single-trace $$ T\overline{T} $$ 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 $$ J\overline{J} $$ 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.- 16 July 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (7) , 1-46
Open AccessThermal partition function of $ {J}_3{\overline{J}}_3 $ deformed AdS3We derive a compact formula for the one-loop, bosonic string partition function of Euclideanized $$ {J}_3{\overline{J}}_3 $$ deformed AdS 3 with periodic Euclidean time as an integral transform of the partition function of the undeformed Euclideanized AdS 3. Such a deformation is interpretable as an irrelevant “single-trace $$ T\overline{T} $$ 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 $$ J\overline{J} $$ 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.