Talks

DAY 1

Keun-Young Kim 

Comments on quantum chaos 

TBA

Chanyong Park

Reconstructing the dual gravity from entanglement entropy

Applying the rule-based method (holography), we study how to reconstruct the dual gravity theory of given  QFT data, especially entanglement entropy. We first attempt to derive a 3-dimensional black hole geometry from the entanglement entropy of a 2-dimensional thermal system composed of two distinct types of matter.  Using the reconstructed black hole geometry, we determine various thermodynamic properties of the thermal system. We further investigate how to rebuild the dual gravity theory of a given entanglement entropy when a relevant operator deforms a UV CFT. After finding the dual deformed geometry, we reconstruct the dual gravity theory admitting the obtained geometric solution.  

Jaydeep Kumar Basak

 Aspects of holographic timelike entanglement entropy

I will show a holographic framework for timelike entanglement entropy (tEE) and analyze its implications in geometries with a general dynamical critical exponent z and hyperscaling violation exponent θ. Within this setup, I will demonstrate that the parameter region consistent with the tEE construction forms a strict subset of the space allowed by the null energy conditions and basic stability criteria. I will further show how holographic tEE behaves in black hole backgrounds, highlighting several characteristic features that distinguish the timelike case from its spatial counterpart.

Yongjun Ahn 

Cosmological pole-skipping, shock waves and quantum chaotic dynamics of de Sitter horizons

We present a systematic analysis of pole-skipping for scalar, Maxwell, and gravitational waves in cosmological spacetimes. Specifically, working in empty de Sitter space and in Schwarzschild-de Sitter black hole geometries, we locate the tower of pole-skipping points of such fields and show that they impose nontrivial constraints on the corresponding bulk two-point functions. Focusing on the gravitational sound channel, we then extract the Lyapunov exponent and butterfly velocities that characterize hypothetical dual many-body quantum chaos at each horizon. These chaotic data precisely match the outcome of a gravitational shock wave calculation, confirming that the relevant pole-skipping points encode high-energy scattering of horizon quanta. Interestingly, the butterfly velocities can become superluminal or imaginary, with the latter signaling a spatially modulated propagation of chaos. Assuming that a holographic dual exists, we translate our results into field theory language and propose that the dual theory can be divided into two entangled sectors that capture the black hole and cosmological horizon degrees of freedom. Our results suggest that the black hole sector becomes increasingly nonlocal as the black hole shrinks and that the cosmological horizon sector exhibits behavior compatible with violations of Hermiticity. Finally, we outline simple microscopic toy models, built from long-range and non-Hermitian deformations of the Double Scaled Sachdev-Ye-Kitaev (DSSYK)-type chains, that realize these features, providing a concrete arena for future exploration.

Kyoung-Bum Huh

Quantum Chaos and Krylov complexity in mixed phase space

Krylov complexity has recently emerged as a new paradigm for characterizing quantum chaos in many-body systems. Recent studies have shown that, in quantum chaotic systems, the Krylov state complexity exhibits a distinct peak during time evolution before settling into a well-understood late-time plateau. In this work, we propose that this Krylov complexity peak (KCP) is a hallmark of quantum chaos and suggest that its height can serve as an effective order parameter. We investigate the Krylov complexity of thermofield double states in systems with mixed phase space, revealing a clear correlation with the Brody distribution, which interpolates between Poisson and Wigner level statistics. Our analysis spans two-dimensional random matrix models featuring (i) GOE-Poisson and (ii) GUE-Poisson transitions, and extends to higher- dimensional systems, including a stringy matrix model (GOE-Poisson) and the mass-deformed SYK model (GUE-Poisson). These results establish Krylov complexity as a powerful diagnostic of quantum chaos, highlight its interplay with level statistics in mixed phase systems, and offer deeper insights into the general properties of quantum chaotic systems.

Jeong-Won Seo 

Ten fold classification by Holographic discrete symmetries

"We present a symmetry-based formulation of discrete symmetries in holography and use it to classify holographic fermionic matter within the Altland–Zirnbauer framework. Starting from a multi-flavor bulk Dirac theory in asymptotically AdS backgrounds, we construct explicit (anti)unitary operators for time reversal , charge conjugation/particle–hole , and their unitary product , including the necessary momentum and coordinate reflections. We emphasize the distinction between the mere existence of an antiunitary map on the Hilbert space and a genuine symmetry that leaves the bulk action and boundary conditions invariant, and we derive the resulting constraints on the boundary source–response map and retarded Green’s function. This provides a practical dictionary that connects bulk symmetry realizations to discrete-symmetry classes of holographic fermion systems and clarifies how internal flavor/orbital structure can implement spatial discrete symmetries in the dual field theory."

DAY 2

Nakwoo Kim

Single Cut or Multi-Cut? : The Case of Chiral N=2 Chern-Simons-Matter Theories

We discuss the large $N$ saddle point equations for $\mathcal{N}=2$ Chern-Simons-matter theories. While the non-chiral cases have been well-understood, the chiral cases had remained unsolved for over 15 years until the recent breakthrough by S.M. Hosseini (arXiv:2510.24837). I will share my own endeavor towards an analytic solution for these chiral theories, including both the excitement and frustration experienced while working with Gemini 3.

Euihun Joung

Worldline model for Higher Spin Gravity

We present a worldline model for higher spin gravity. By computing 2pt and 3pt functions of local spin s operators, we show that our model correctly reproduces the results of type A and type B Vasiliev theory, which are dual to free boson and free fermion theory. 

Junggi Yoon

TBA

TBA

Byoungjoon Ahn

Probing the Hierarchy of Genuine Multipartite Entanglement with Generalized Latent Entropy

We propose a generalized Latent Entropy as a measure of genuine multipartite entanglement in pure n-party quantum states. The measure satisfies the axioms of a valid GME monotone, naturally orders k-uniform states, and is maximized by absolutely maximally entangled states. We study its behavior in Haar-random states and apply it to various SYK models, demonstrating its effectiveness in probing multipartite entanglement and its response to model deformations.

Yunseok Seo

D-instanton effects on the holographic Weyl semimetal

We study the holographic Weyl semimetal model from a top-down approach. In this model, the surface state of the Weyl semimetal changes from a metallic state to an insulator by changing the Weyl point in momentum space. We introduce D-instanton in themodel and investigate the impurity effect on the metallic state holographically.

Kyung Kiu Kim

Rotating End of the World

 In this work, we study a gravity dual to a two-dimensional BCFT with momentum flux. The resultant configuration is a rotating spacetime in the rotating BTZ black hole. The flux needs a source-boundary and a sink-boundary. In the bulk, these correspond to an end-of-the-world (EOW) brane annihilating spacetime and an EOW brane creating specetime. Furthermore, we find possible physical configurations inside the horizon.

Miok Park 

TBA

TBA

Hyun-Sik Jeong 

Neural Network-Based Methods for Inverse Problems in Holography

Holography (AdS/CFT) provides a powerful framework for studying the quantum nature of gravity and strongly coupled quantum systems. This talk showcases how deep neural networks can address inverse problems in holography: specifically, reconstructing bulk gravity models from boundary observables. By integrating holography with physics-informed neural networks, we show that strongly coupled systems, from QCD-like theories to condensed-matter models and entanglement-based setups, can be analyzed in a data-driven and robust way. The aim is to demonstrate how machine-learning methods enable stable, consistent reconstructions and offer new insights that complement traditional holographic approaches.

Ashutosh Tripathi  

Learning Higher-Derivative Holography from QGP Transport Data with PINNs

"We present a physics-informed machine-learning framework to infer effective holographic dynamics directly from temperature-dependent shear-viscosity data of the quark–gluon plasma. Concretely, we consider a bottom-up Einstein–dilaton model augmented by a dilaton-dependent higher-derivative (Gauss–Bonnet / curvature-squared) sector. This makes the transport observable eta/s a nontrivial functional of the background solution and the higher-derivative coupling evaluated at the black-hole horizon. This structure enables broad classes of (eta/s(T)) profiles to be reproduced by appropriate choices of the dilaton potential V(\phi) and coupling G(\phi). 

Our approach treats the bulk equations as constraints and trains a physics-informed neural network (PINN) that simultaneously (i) solves the coupled bulk system and (ii) performs inverse modeling of {V(\phi), G(\phi) from \eta/s(T). The loss combines equation-of-motion residuals with data-misfit terms defined on a controlled temperature window. Explicit temperature re-mappings ensure that datasets defined on different (T_c) conventions occupy a consistent model input domain. We demonstrate stable reconstructions across multiple (\eta/s) targets and discuss how the learned V(\phi), g(\phi) encode the required temperature dependence of transport in a higher-derivative holographic QCD setup."

DAY 3

XianHui Ge

TBA

TBA

Taewon Yuk

Holographic Mean Field Theory Classification via Conductivity: Vector Order Parameter

TBA

Debabrata Ghorai

Holographic transport from quantum geometry

In this talk, we present a new method to compute holographic transport directly from the fermionic retarded Green’s function using the quantum geometric tensor (QGT). This framework links fermionic spectral functions to transport in strongly coupled systems, with the black-hole background effectively playing the role of a Fermi–Dirac distribution. We demonstrate an insulator–to–metal transition from the DC conductivity.

Sang-Jin Sin 

Mean field theory and strange metal 

I will discuss the holographic mean field theory and mechanism of strange metal.