Ji Hoon Lee
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Ji Hoon Lee has a total of 7 co-authors. Here are the top co-authors by number of shared publications:
- Ashish Shukla
Saha Institute of Nuclear physics
2 shared publications - Davide Gaiotto
Perimeter Institute for Theoretical Physics
2 shared publications - Dominik Neuenfeld
University of Würzburg
2 shared publications - Jingxiang Wu
Mathematical Institute University of Oxford Andrew Wiles Building Radcliffe Observatory Quarter Woodstock Road OX2 6GG Oxford U.K
1 shared publication - Olga Papadoulaki
CPHT, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris
1 shared publication - Panos Betzios
Ghent University
1 shared publication
Latest Publications
- Open Access
- 22 June 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (6) , 224
Bubbling wormholes and matrix models
A bstract: The thermofield double state entangles two copies of a CFT via a sum over energy eigenstates and is dual to the two-sided eternal black hole. We explore an analogous construction using sums over gauge group representations of half-BPS Wilson loops in multiple copies of U ( N ) $$ \mathcal{N} $$ = 4 super Yang-Mills. These sums act as delta function-like operators that correlate the eigenvalues of the corresponding half-BPS matrix models. We suggest that the holographic duals are “bubbling wormhole” geometries: multi-covers of AdS 5 × S 5 whose conformal boundary consists of multiple four-spheres intersecting on a common circle. We analyze the matrix model free energy, discuss its bulk interpretation, and study probe loops in these backgrounds.- 22 June 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (6) , 224
Open AccessBubbling wormholes and matrix models
A bstract: The thermofield double state entangles two copies of a CFT via a sum over energy eigenstates and is dual to the two-sided eternal black hole. We explore an analogous construction using sums over gauge group representations of half-BPS Wilson loops in multiple copies of U ( N ) $$ \mathcal{N} $$ = 4 super Yang-Mills. These sums act as delta function-like operators that correlate the eigenvalues of the corresponding half-BPS matrix models. We suggest that the holographic duals are “bubbling wormhole” geometries: multi-covers of AdS 5 × S 5 whose conformal boundary consists of multiple four-spheres intersecting on a common circle. We analyze the matrix model free energy, discuss its bulk interpretation, and study probe loops in these backgrounds. - Top Cited PapersOpen Access
- 5 August 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (8) , 1-65
The giant graviton expansion
A bstract: We propose and test a novel conjectural relation satisfied by the superconformal index of maximally supersymmetric U( N ) gauge theory in four dimensions. Analogous relations appear to be also valid for the superconformal indices of a large collection of other gauge theories, as well as for a broad class of index-like generating functions. The relation expresses the finite N index as a systematic series of corrections to a large N answer. Individual corrections have an holographic interpretation as the analytic continuation of contributions from “giant graviton” branes fixed by a specific symmetry generator.
- 5 August 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (8) , 1-65
Top Cited PapersOpen AccessThe giant graviton expansion
A bstract: We propose and test a novel conjectural relation satisfied by the superconformal index of maximally supersymmetric U( N ) gauge theory in four dimensions. Analogous relations appear to be also valid for the superconformal indices of a large collection of other gauge theories, as well as for a broad class of index-like generating functions. The relation expresses the finite N index as a systematic series of corrections to a large N answer. Individual corrections have an holographic interpretation as the analytic continuation of contributions from “giant graviton” branes fixed by a specific symmetry generator.
- Open Access
- 28 February 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (2) , 1-40
Trace relations and open string vacua
We study to what extent, and in what form, the notion of gauge-string duality may persist at finite N. It is shown, in the half-BPS sector, that the states of D3 giant graviton branes in AdS5 × S 5 are holographically dual to certain auxiliary ghosts that compensate for finite N trace relations in U(N) $$ \mathcal{N} $$ = 4 super Yang-Mills. The complex formed from spaces of states of bulk D3 giants is observed to furnish a BRST-like resolution of the half-BPS Hilbert space of U(N) $$ \mathcal{N} $$ = 4 SYM at finite N. We argue that the identification between the states of certain bulk D-branes and the auxiliary ghosts in the boundary holds rather generally at vanishing ’t Hooft coupling λ = 0. We propose that a complex, which furnishes a BRST-like resolution of the finite N Hilbert space of a boundary U(N) gauge theory at λ = 0, should be identified as the space of states of the dual string theory in the α′ → ∞ limit. The Lefschetz trace formula provides the holographic map in this regime, where bulk observables are computed by taking the alternating sum of the expectation values in an ensemble of states built on each open string vacuum. The giant graviton expansion is recovered and generalized in a limit of the resolution.- 28 February 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (2) , 1-40
Open AccessTrace relations and open string vacua
We study to what extent, and in what form, the notion of gauge-string duality may persist at finite N. It is shown, in the half-BPS sector, that the states of D3 giant graviton branes in AdS5 × S 5 are holographically dual to certain auxiliary ghosts that compensate for finite N trace relations in U(N) $$ \mathcal{N} $$ = 4 super Yang-Mills. The complex formed from spaces of states of bulk D3 giants is observed to furnish a BRST-like resolution of the half-BPS Hilbert space of U(N) $$ \mathcal{N} $$ = 4 SYM at finite N. We argue that the identification between the states of certain bulk D-branes and the auxiliary ghosts in the boundary holds rather generally at vanishing ’t Hooft coupling λ = 0. We propose that a complex, which furnishes a BRST-like resolution of the finite N Hilbert space of a boundary U(N) gauge theory at λ = 0, should be identified as the space of states of the dual string theory in the α′ → ∞ limit. The Lefschetz trace formula provides the holographic map in this regime, where bulk observables are computed by taking the alternating sum of the expectation values in an ensemble of states built on each open string vacuum. The giant graviton expansion is recovered and generalized in a limit of the resolution. - Open Access
- 23 November 2022
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2022 (11) , 1-54
Exact stringy microstates from gauge theories
We study how the microstates of BPS sectors in string theory are organized in the dual U(N) gauge theory. The microstates take the form of a coherent sum of stacks of branes and their open/closed string excitations. We propose a prescription to holographically construct the indices of string/brane configurations by analyzing the modifications of determinant operators in gauge theory. The string/brane configurations should be interpreted in the tensionless limit, but their indices are well-defined at finite N. In various examples, we provide evidence that a sum, of the giant graviton-type recently proposed in the literature, over all such configurations gives the finite N gauge theory index. Finally, we discuss how these microstates assemble in the BPS Hilbert space and in what circumstances the branes can form bound states to produce black hole degeneracies.
- 23 November 2022
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2022 (11) , 1-54
Open AccessExact stringy microstates from gauge theories
We study how the microstates of BPS sectors in string theory are organized in the dual U(N) gauge theory. The microstates take the form of a coherent sum of stacks of branes and their open/closed string excitations. We propose a prescription to holographically construct the indices of string/brane configurations by analyzing the modifications of determinant operators in gauge theory. The string/brane configurations should be interpreted in the tensionless limit, but their indices are well-defined at finite N. In various examples, we provide evidence that a sum, of the giant graviton-type recently proposed in the literature, over all such configurations gives the finite N gauge theory index. Finally, we discuss how these microstates assemble in the BPS Hilbert space and in what circumstances the branes can form bound states to produce black hole degeneracies.
- Open Access
Exact Stringy Microstates from Gauge Theories
We study how the microstates of BPS sectors in string theory are organized in the dual $U(N)$ gauge theory. The microstates take the form of a coherent sum of stacks of branes and their open/closed string excitations. We propose a prescription to holographically construct the indices of string/brane configurations by analyzing the modifications of determinant operators in gauge theory. The string/brane configurations should be interpreted in the tensionless limit, but their indices are well-defined at finite $N$. In various examples, we provide evidence that a sum, of the giant graviton-type recently proposed in the literature, over all such configurations gives the finite $N$ gauge theory index. Finally, we discuss how these microstates assemble in the BPS Hilbert space and in what circumstances the branes can form bound states to produce black hole degeneracies.Open AccessExact Stringy Microstates from Gauge Theories
We study how the microstates of BPS sectors in string theory are organized in the dual $U(N)$ gauge theory. The microstates take the form of a coherent sum of stacks of branes and their open/closed string excitations. We propose a prescription to holographically construct the indices of string/brane configurations by analyzing the modifications of determinant operators in gauge theory. The string/brane configurations should be interpreted in the tensionless limit, but their indices are well-defined at finite $N$. In various examples, we provide evidence that a sum, of the giant graviton-type recently proposed in the literature, over all such configurations gives the finite $N$ gauge theory index. Finally, we discuss how these microstates assemble in the BPS Hilbert space and in what circumstances the branes can form bound states to produce black hole degeneracies. - Open Access
- 20 October 2022
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2022 (10) , 1-53
Bounds on gravitational brane couplings and tomography in AdS3 black hole microstates
We study information theoretic properties of planar black hole microstates in 2 + 1 dimensional asymptotically anti-de Sitter spacetime, modeled by black holes with an end-of-the-world brane behind the horizon. The von Neumann entropy of sufficiently large subregions in the dual CFT exhibits a time-dependent phase, which from a doubly-holographic perspective corresponds to the appearance of quantum extremal islands in the brane description. Considering the case where dilaton gravity is added to the brane, we show that tuning the associated couplings affects the propagation of information in the dual CFT state. By requiring that information theoretic bounds on the growth of entanglement entropy are satisfied in the dual CFT, we can place bounds on the allowed values of the couplings on the brane. Furthermore, we initiate the study of brane tomography, by showing how subleading corrections to the entanglement velocity can be used to learn about the properties of the brane as well as any gravitational dynamics localized on it.
- 20 October 2022
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2022 (10) , 1-53
Open AccessBounds on gravitational brane couplings and tomography in AdS3 black hole microstates
We study information theoretic properties of planar black hole microstates in 2 + 1 dimensional asymptotically anti-de Sitter spacetime, modeled by black holes with an end-of-the-world brane behind the horizon. The von Neumann entropy of sufficiently large subregions in the dual CFT exhibits a time-dependent phase, which from a doubly-holographic perspective corresponds to the appearance of quantum extremal islands in the brane description. Considering the case where dilaton gravity is added to the brane, we show that tuning the associated couplings affects the propagation of information in the dual CFT state. By requiring that information theoretic bounds on the growth of entanglement entropy are satisfied in the dual CFT, we can place bounds on the allowed values of the couplings on the brane. Furthermore, we initiate the study of brane tomography, by showing how subleading corrections to the entanglement velocity can be used to learn about the properties of the brane as well as any gravitational dynamics localized on it.
- Open Access
Bounds on gravitational brane couplings and tomography in AdS3 black hole microstates
We study information theoretic properties of planar black hole microstates in 2 + 1 dimensional asymptotically anti-de Sitter spacetime, modeled by black holes with an end-of-the-world brane behind the horizon. The von Neumann entropy of sufficiently large subregions in the dual CFT exhibits a time-dependent phase, which from a doubly-holographic perspective corresponds to the appearance of quantum extremal islands in the brane description. Considering the case where dilaton gravity is added to the brane, we show that tuning the associated couplings affects the propagation of information in the dual CFT state. By requiring that information theoretic bounds on the growth of entanglement entropy are satisfied in the dual CFT, we can place bounds on the allowed values of the couplings on the brane. Furthermore, we initiate the study of brane tomography, by showing how subleading corrections to the entanglement velocity can be used to learn about the properties of the brane as well as any gravitational dynamics localized on it.
Open AccessBounds on gravitational brane couplings and tomography in AdS3 black hole microstates
We study information theoretic properties of planar black hole microstates in 2 + 1 dimensional asymptotically anti-de Sitter spacetime, modeled by black holes with an end-of-the-world brane behind the horizon. The von Neumann entropy of sufficiently large subregions in the dual CFT exhibits a time-dependent phase, which from a doubly-holographic perspective corresponds to the appearance of quantum extremal islands in the brane description. Considering the case where dilaton gravity is added to the brane, we show that tuning the associated couplings affects the propagation of information in the dual CFT state. By requiring that information theoretic bounds on the growth of entanglement entropy are satisfied in the dual CFT, we can place bounds on the allowed values of the couplings on the brane. Furthermore, we initiate the study of brane tomography, by showing how subleading corrections to the entanglement velocity can be used to learn about the properties of the brane as well as any gravitational dynamics localized on it.
- Open Access
- 28 April 2021
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2021 (4) , 1-63
Integrable Kondo problems
We discuss the integrability and wall-crossing properties of Kondo problems, where an 1d impurity is coupled to a 2d chiral CFT and triggers a defect RG flow. We review several new and old examples inspired by constructions in four-dimensional Chern-Simons theory and by affine Gaudin models.
- 28 April 2021
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2021 (4) , 1-63
Open AccessIntegrable Kondo problems
We discuss the integrability and wall-crossing properties of Kondo problems, where an 1d impurity is coupled to a 2d chiral CFT and triggers a defect RG flow. We review several new and old examples inspired by constructions in four-dimensional Chern-Simons theory and by affine Gaudin models.