Gauge Gravity Duality 2024
Sanya, Hainan, China
Gauge/Gravity Duality has established itself as a significant link between gravitation, quantum field theory, and many other established research fields such as condensed matter, QCD, and quantum information, creating a novel interdisciplinary playground for innovative research. The aim of the conference is to explore all aspects of gauge/gravity duality, both applied and theoretical,and to generate an extensive exchange of ideas between world-wide experts in the field. Gauge-gravity duality 2024 will provide a modern overview of recent developments and will pose the basis for future discoveries. The conference will take place in the beautiful Tsinghua Sanya International Mathematics Forum (TSIMF) between Saturday 30th of November and Wednesday 4th of December.
Previous conferences in this series have been successfully held in CERN (2021), Würzburg (2018), Florence (2015), Munich (2013), and after a Covid break, it is time to make gauge-gravity duality great again!
Scientific Organizers
Matteo Baggioli (SJTU), Rong-Gen Cai (ITP, CAS and NBU), Johanna Erdmenger (JMU), Xian-Hui Ge (SHU), Elias Kiritsis (APC, Paris and Crete U.), Li Li (ITP, CAS), Wei-Jia Li (DUT), Ya-Wen Sun (UCAS)
This conference is supported by National Natural Science Foundation of China (NSFC).
Registration fee
The registration fee is 200 USD/1500 RMB, including meal and reception, and will be paid at the venue.
Important dates
25th October, 2024: Deadline for the abstract submission
30th October, 2024: Deadline for the registration
29th November, 2024: Registration day on site
On registration day, we will arrange shuttle buses at the Sanya Phoenix International Airport (IATA: SYX). The volunteers will pick you up at the arrival gate and take you to the shuttle bus. Please follow their guidance.
- Akash Singh
- Alexey Koshelev
- Amos Yarom
- Andre Oliveira Pinheiro
- Anirban Roy Chowdhury
- Anna Tokareva
- Ayan Mukhopadhyay
- Bin Chen
- Blaise Goutéraux
- Byoungjoon Ahn
- Chaymae Karam
- Chen Bai
- Cheng Peng
- Chengjia Chen
- chengyuan lu
- Chenqingshui Huang
- Chuan-Yi Wang
- Ci Zhuang
- Daniel Arean
- Diana Mandar
- Dr. Huang
- Duoen Shou
- Elias Kiritsis
- Fei-Yu Chen
- Feiyu Deng
- Gabriel Arenas-Henriquez
- Guang Zhuo Peng
- Haitang Yang
- Hamed Adami
- Hao Li
- Hao Shan
- Hao Xu
- HaoTian Sun
- Haoyu Sun
- Haoyuan Li
- Hiwa Ahmed
- hong ma
- Hong-Bo Jin
- Hongguang Li
- hongsheng zhang
- huabi zeng
- James Brister
- Jia-Rui Sun
- JianXin Lu
- Jie Ren
- Jie Zhu
- Jie-qiang Wu
- Jieci wang
- Jiliang Jing
- Jin Wang
- Jun Feng
- Jun Nian
- Jun-Bao Wu
- Jun-Kun Zhao
- Karl Landsteiner
- Keun-Young Kim
- Kilar Zhang
- kui cao
- Lei Li
- Li Li
- LING YAN HUNG
- Ling-Long Gao
- Ling-Zheng Xia
- Liqiang Zhu
- Liqing Fang
- Long Cheng
- LongQi Shao
- Matteo Baggioli
- Matti Jarvinen
- Mei-Ning Duan
- Miguel Angel Martin Contreras
- Mikel Sanchez Garitaonandia
- Minyong Guo
- Navid Abbasi
- Pau Garcia Romeu
- Pei Zheng
- Peng Cheng
- Peng Yang
- Peng-Ju Hu
- Qian Shen
- Qiang Wen
- Qiyuan Pan
- René Meyer
- Robert de Mello Koch
- Robert Myers
- Rongxin Miao
- Rui-Yun Guo
- Run-Qiu Yang
- Sang-Jin Sin
- Shan-Ming Ruan
- Shanquan Lan
- Shin Nakamura
- Shoucheng Wang
- Shu Lin
- Shuta Ishigaki
- SiWei Han
- Sizheng Cao
- Song He
- Songbai Chen
- Surojit Dalui
- Tadashi Takayanagi
- Tie-Guang Zi
- Viktor Jahnke
- Wanxiang Fan
- Wei Li
- Wei Wang
- Wei-Jia Li
- Weibo Mao
- Wen-Bin Pan
- Wencong Gan
- Wenjing Chen
- Wuzhong Guo
- Xian Gao
- XianHui Ge
- Xiao-Long Liu
- Xiao-Shuai Wang
- Xiaoyang Huang
- Xin-Meng Wu
- Xin-Xiang Ju
- Xinan Zhou
- Xing Huang
- Xiongying Guo
- Xuanting Ji
- Xun Xue
- Ya-Wen Sun
- Yan Liu
- Yan-Qing Zhao
- Yang Li
- Yang Zhao
- Yang Zhou
- Yanqi Wang
- Yanyan Bu
- Yi Li
- Yi Ling
- Yi Yin
- Yi-Li Wang
- Yi-Ping Si
- Yi-Qiang Du
- Yidian(亦点) Chen(陈)
- Ying Yang
- Yizhou Lu
- Yong Xiao
- yong-qiang Wang
- Yongjun Ahn
- Yongjun Xu
- Yu Tian
- Yu-Qi Lei
- Yu-Sen An
- Yu-Xuan Li
- Yu-Xuan Zhang
- Yuanceng Xu
- Yunseok Seo
- Yuping An
- Zehua Tian
- Zhaojie Xu
- Zhen-Ming Xu
- Zheng Jiang
- Zheng-Quan Cui
- Zhenhan Jin
- Zhenkang Lu
- 勋 陈
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08:15
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08:45
Registration 30m
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08:45
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09:00
Welcome 15m Room A211 (TSIMF)
Room A211
TSIMF
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09:00
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12:20
Day1 Main venue: Morning Session Room A211 (TSIMF)
Room A211
TSIMF
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09:00
Aspects of Holographic Pseudo Entropy 40m
TBA
Speaker: Tadashi Takayanagi (YITP, Kyoto U.) -
09:40
QCD Equation of State from Holographic method 40m
I will show the results of QCD equation of state under finite temperature, finite baryon density and fast rotation in the framework of dynamical holographic QCD model, and comparing with lattice QCD calculations.
Speaker: Mei Huang (University of Chinese Academy of Sciences) -
10:20
Coffee Break 30m
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10:50
The Dynamics of Entanglement Entropy in CFT: Einstein Equation 30m
We show that the dynamics of entanglement entropy in CFT are precisely Einstein equation. The QFT RG equation turns out to be a geometric identity. In the entropy generated geometry, a covariant Klein-Gordon equation is also found. We are thus led to propose some new interpretation about Gauge/Gravity duality.
Speaker: Hai-Tang Yang (Sichuan University ) -
11:20
Hydrodynamic Long-time tails in large-N systems 30m
In holographic systems with large N, the hydrodynamic derivative expansion converges in momentum space. However, the first subleading effect in the 1/N expansion results in a long-time tail in the hydrodynamic response, leading to breakdown of the derivative expansion. This talk explores how these subleading corrections can be systematically incorporated by modifying the derivative expansion, thereby addressing the impact of long-time tails on hydrodynamic behavior in large-N systems.
Speaker: Navid Abbasi (Lanzhou University ) -
11:50
Spin polarization in strongly couple fluid 30m
Recently there has been growing interest in spin polarization in relativistic heavy ion collisions. It is known that spin can be induced by different hydrodynamic gradients. So far most theoretical frameworks for spin polarization is based on quasi-particles, which leads to the understanding that spin polarization comes from modified distribution and modified fluctuation-dissipation relation. By working in the strong coupling limit using holographic fermion in hydrodynamic background, we find that the spin can also be induced by modified spectral function. In particular, we find Landau damping type of excitation gains polarization in the hydrodynamic background.
Speaker: Shu Lin (Sun Yat-sen University)
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09:00
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12:20
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14:20
Lunch 2h
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14:20
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18:50
Day1 Main venue: Afternoon Session Room A211 (TSIMF)
Room A211
TSIMF
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14:20
Spin currents and their uses 40m
I will explain what a spin current is, why it is important in describing heavy ion collisions, and why a holographic spin current would be useful. I will then describe the challenges in constructing a holographic spin current and how they are addressed.
Speaker: Amos Yarom (Technion) -
15:00
New physics from non-equilibrium cold atoms by holography 40m
Holography has emerged as a pivotal tool in investigating the nonequilibrium physics of quantum many-body systems, particularly offering a systematic approach to stability and dynamical phase transitions through the theory of black hole perturbations and dynamics. This report aims to present some exciting recent advancements in this interdisciplinary field, with a focus on recent works concerning quantum vortex splitting and dissipative discrete time crystals.
Speaker: Yu Tian (UCAS) -
15:40
Holographic thermal correlators from recursions 30m
We calculate holographic thermal correlators using a recurrence relation of $\{a_n\}$ at $n\to\infty$, building on recent advances in the connection formula for the Heun equation. We consider two gravitational solutions that correspond to distinct states in different subsectors of $\mathcal{N}=4$ super-Yang-Mills theory at finite temperature and density. The first solution is the Reissner-Nordstr\"{o}m-AdS$_5$ black hole, which has finite entropy at zero temperature. The second solution is a charged dilatonic black hole in AdS$_5$, which has zero entropy at zero temperature. In both cases, we perturb the system with a charged scalar field and express the perturbation equation in terms of the Heun equation. We find interesting moving patterns of the poles of the correlators. We discuss the relation between the recurrence relation and the Virasoro conformal block as two equivalent approaches to write the connection formula for the Heun equation.
Speaker: Jie Ren (Sun Yat-sen University) -
16:10
Coffee Break 30m
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16:40
Bulk reconstruction and the fine structure of entanglement 30m
Bulk reconstruction in the AdS/CFT correspondence is aimed to construct the bulk gravity from the information of the boundary CFT. While the fine structure of entanglement are quantities which can unravel more refined infromation about the quantum entanglement. In this talk, we will introduce our recent works on these two topics and will show that the fine structure of entanglement, such as entanglement contour, Renyi contour and their holographic duals can provide important tools for bulk reconstruction in gauge/gravity duaity.
Speaker: Jia-Rui Sun (Sun Yat-Sen University) -
17:10
String duality applications on compact stars in gravitational wave observation 30m
For black holes, we apply the Seiberg-Witten (SW)/Quasinormal Modes (QNM) correspondence to analytically calculate the black hole QNM and superradiance frequencies. For neutron stars, two types of holographic QCD is used to extract the equation of state. We then discuss the gravitational wave observation interpretations and restrictions on those compact star models.
Speaker: Kilar Zhang (Shanghai University) -
17:40
Application of machine learning in the holographic QCD 30m
In this talk, I will introduce our recent works on the application of machine learning in the holographic QCD. Using the machine learning, we can construct the holographic model with lattice EOS. We calculated the heavy quark potential, jet queching parameters and so on based on our model. Combining the machine learning with hadron spectrum, we can also construct the holographich model which can describe the spectrum well.
Speaker: Xun Chen (University of South China)
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14:20
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18:10
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20:00
Dinner 1h 50m
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08:15
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08:45
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09:00
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12:20
Day2 Main venue: Morning Session¶ Room A211 (TSIMF)
Room A211
TSIMF
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09:00
(Confining) Holographic QFTs on AdS 40m
We consider three related topics: (a) Holographic quantum field theories on AdS spaces. (b) Holographic interfaces of flat space QFTs. (c) Wormholes connecting generically different QFTs. We investigate in a concrete example how the related classical solutions explore the space of QFTs and we construct the general solutions that interpolate between the same or different CFTs with arbitrary couplings. The solution space contains many exotic RG flow solutions that realize unusual asymptotics, as boundaries of different regions in the space of solutions. We find phenomena like "walking" flows and the generation of extra boundaries via "flow fragmentation". We then consider holographic quantum field theories that confine (in flat space), on a fixed AdS space. The space of holographic solutions for such theories is constructed and three types of regular solutions are found. Theories with two AdS boundaries provide interfaces between two confining theories. Theories with a single AdS boundary correspond to ground states of a single confining theory on AdS. We find solutions without a boundary, whose interpretation is not obvious. There is also a special limiting solution that oscillates an infinite number of times around the UV fixed point. We analyze in detail the holographic dictionary for the one-boundary solutions and compute the free energy. No (quantum) phase transitions are found when we change the curvature. We find an infinite number of pure vev solutions, but no CFT solution without a vev. We also compute the free energy of the interface solutions. We find that the product saddle points have always lower free energy than the connected solutions. This implies that in such interfaces, normalized cross-correlators vanish exponentially in N2c.
Speaker: Elias Kiritsis (APC, Paris and Crete U.) -
09:40
Discussion & memorial of Jan Zannen 40mSpeaker: All participants
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10:20
Coffee Break+Conference Photo 30m
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10:50
The extended hydrodynamics and holography 30m
We report recent progress in extending relativistic hydrodynamics that is largely inspired by the gauge/gravity duality. First, we present a simple but nontrivial extension of Muller-Israel-Stewart (MIS) theory, namely MIS*, and demonstrate that it describes non-hydrodynamic response for both kinetic theory and strongly coupled super-Yang Mills theory. Second, we construct an effective field theory describing holography liquid with one conserved U(1) charge. In addition, such a theory includes K number of hidden local symmetries that are broken spontaneously. If K goes to the infinity limit, it reproduces the quasi-normal spectrum from holography.
Refs: Weiyao Ke, Yi Yin, JHEP 05 (2024) 171; Phys.Rev.Lett. 130 (2023) 21, 212303; Xin An, Micheal Heller, Robbe Brants , Yi Yin, in progress
Speaker: Yi Yin (Chinese University of Hong Kong (Shenzhen)) -
11:20
Three-point Functions in ABJM Theory and Integrable Boundary States 30m
We investigate the correlators of three single-trace operators in Aharony-Bergman-Jafferis-Maldacena (ABJM) theory from the perspective of integrable boundary states. Specifically, we focus on scenarios where two operators being 1/3-BPS and the entire correlation function is considered within the twisted-translated frame. The correlator can be expressed as the overlap between a boundary state and a Bethe state. It is found that the boundary state formed by the two 1/3-BPS operators is integrable only when the number of Wick contractions between the non-BPS operator and one of the 1/3-BPS operators is 0 or 1. We compute the overlaps for the integrable cases utilizing the symmetries preserved by the correlators. This talk is based on work done with Peihe Yang.
Speaker: Jun-Bao Wu (Tianjin University) -
11:50
Deep learning bulk spacetime from boundary quantum data 30m
We utilize a deep learning approach to infer the bulk spacetime from boundary data, including optical conductivity and entanglement entropy. This method is particularly intriguing as it models AdS space using a deep neural network framework. Furthermore, our approach is universal, making it applicable to a wide range of physics problems that involve differential equations and integrals
Speaker: Keun-Young Kim (GIST)
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09:00
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12:20
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14:20
Lunch 2h
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14:20
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17:30
Day 2: Parallel session I Room A211 (TSIMF)
Room A211
TSIMF
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14:20
Isospectrality in hadronic bottom-up models 30m
In physics, isospectrality deals with two Hamiltonians with the same energy spectrum. This discussion was developed up to the early 1980s, particularly in the context of the Darboux transform, a mathematical technique used to generate new solutions to the Schrödinger equation in supersymmetric quantum mechanics. In bottom-up holography, one of the key ingredients is the dilaton field, which sets the confinement and the mass spectrum scale. In this talk, we will discuss how isospectrality and configurational entropy allow us to explore dilaton-based models.
Speaker: Miguel Angel Martin Contreras (University of South China) -
14:50
Reflected multi-entropy and its holographic dual 30m
We propose a new multipartite measure for mixed states called "reflected multi-entropy" and present its holographic dual within the AdS/CFT correspondence, demonstrating its validity through calculations in AdS3/CFT2 at both zero and finite temperatures. This talk is based on arXiv:2410.08546.
Speaker: Yang Zhou (Fudan U.) -
15:20
Pattern formation from Gauge/Gravity duality 30m
In the framework of the AdS/CFT correspondence, we find a neutral complex scalar field dynamics in a 2+1 dimensional black hole background which can provide a scheme for studying the pattern formation process in 1+1 dimensional reaction-diffusion systems. The patterns include plane wave, defect turbulence, phase turbulence, spatio-temporal intermittency where defect chaos coexists with stable plane wave, and coherent structures. A phase diagram is obtained by studying the linear instability of the plane wave solutions to determine the onset of the holographic version of the BFN instability. Near the critical temperature the holographic model is dual to the one-dimensional complex Ginzburg-Landau equation (CGLE), which has been studied extensively in reaction-diffusion systems. While at low temperature the holographic theory is different from CGLE.
Speaker: Hua-Bi Zeng (Center for Theoretical Physics, Hainan University) -
15:50
Coffee Break 30m
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16:20
On the second order quasi-normal modes for an AdS black brane 20m
We study the second order gravitational perturbations in an AdS black brane background with Dirichlet condition on the AdS boundary and ingoing condition on the horizon. A second order quasi-normal mode is sourced by two first order quasi-normal modes. We obtain the equation of motion for the second order modes through a gauge invariant formalism and calculate numerically the ratio of amplitude between the second order mode and the product of the two linear modes in the source. The ratio of amplitude are found to be of order one in general. We also discuss about the implication of this non-linear effect on the dual field theory living on the boundary.
Speaker: Wen-Bin Pan (Institute of High Energy Physics, Chinese Academy of Sciences) -
16:40
Quantum Corrections to Quasi-Normal Modes of Near-Extremal Black Holes 20m
Quasi-normal modes are intrinsic properties of black holes and important messages carried by gravitational waves. For near-extremal black holes with very low temperatures, the quantum gravity effects become nonnegligible, consequently modifying the quasi-normal modes. For a 4D near-extremal Reissner-Nordström black hole, its quantum gravity fluctuations should manifest in the near-horizon AdS_2 region, which can be studied within the framework of the nearly AdS_2 Jackiw-Teitelboim gravity. In this talk, I will discuss the quantum corrections to the quasi-normal modes of a 4D near-extremal Reissner-Nordström black hole via this mechanism.
Speaker: Zheng Jiang (ICTP-AP) -
17:00
Bulk metric reconstruction by pole-skipping points 20m
We propose that the exterior of a static, planar symmetric black hole in the bulk, can be analytically reconstructed from the infinite pole-skipping points of the boundary Green's function for a probe scalar operator by solving a set of linear equations. Furthermore, our reconstruction method reveals that only a subset of pole-skipping points are independent, while most are governed by an equal number of homogeneous polynomial identities.
Speaker: Zhen-Kang Lu (Shanghai University)
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14:20
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14:20
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17:30
Day 2: Parallel session II Room A110 (TSIMF)
Room A110
TSIMF
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14:20
Fundamental string from 3D gravity , entanglement and quantum thermodynamics 30m
I will discuss how the Nambu-Goto equation emerges from pure three dimensional gravity with or without a cosmological constant. This does not generalize to co-dimension one branes in higher dimensions. In the context of AdS3/CFT2, a junction with a fundamental string is dual to an interface, and the corresponding solution of the Nambu-Goto equation can be decoded from the time-reparametrization across the interface. I will discuss general constructions of such junctions which realize quantum engines and elementary quantum processors. Furthermore, I will discuss how the junctions realize different types of entanglement, and study the quantum thermodynamics of the corresponding quantum channels via the quantum null energy condition. The latter tells us which junctions cannot be realized physically from the locality and unitarity of the dual field theory.
Based on: JHEP 09 (2024) 013, Phys.Rev.Lett. 129 (2022) 19, 19, Phys.Rev.Lett. 128 (2022) 19, 191602, and upcoming papersSpeaker: Ayan Mukhopadhyay (Instituto de Fisica, Pontificia Universidad Catolica de Valparaiso) -
14:50
D-commuting SYK model: building quantum chaos from integrable blocks 30m
We construct a new quantum chaotic model by combining multiple copies of integrable commuting SYK models. As each copy of the commuting SYK model does not commute with others, this construction breaks the integrability of each commuting SYK, and the family of models demonstrates the emergence of quantum chaos. We study the spectrum of this model analytically in the double-scaled limit. As the number of copies tends to infinity, the spectrum becomes compact and equivalent to the regular SYK model. For finite $d$ copies, the spectrum is close to the regular SYK model in UV but has an exponential tail $e^{E/T_c}$ in the IR. We identify the reciprocal of the exponent in the tail as a critical temperature $T_c$, above which the model should be quantum chaotic. $T_c$ monotonically decreases as $d$ increases, which expands the chaotic regime over the non-chaotic regime. We propose the existence of a phase transition around $T_c$, and the dynamics should be very different in two phases. We further carry out numeric analysis at finite $d$, which supports our proposal.
Speaker: Cheng Peng (UCAS, KITS) -
15:20
Operator Spectral Statistics, Chaos, and Asymptotic Freeness in Quantum Many-Body Systems 20m
We systematically investigate the {\it spectral statistics of operators} in quantum many-body systems, focusing on their connections to quantum chaos and free probability theory. Specifically, we numerically analyze the mixed-field Ising model with disorder, the Sachdev-Ye-Kitaev (SYK) model, and a random unitary model, using direct diagonalization to study the eigenvalue density, nearest-neighbor level spacing statistics, and $r$-parameter statistics. Our results show that the dynamics can be classified as chaotic, integrable, or near-integrable based on the asymptotic freeness of the fundamental operators of the theory, leading to universal behavior in the eigenvalue density of certain combinations of operators. We also discuss the implications of these findings for correlation functions and how the concept of freeness connects different manifestations of quantum chaotic behavior. Finally, we assess the utility of the spectral statistics of out-of-time-order operators in diagnosing chaos across different dynamical regimes.
Speaker: Viktor Jahnke (Gwangju Institute of Science and Technology) -
15:40
Coffee Break 30m
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16:10
Mutual information of subsystems and the Page curve of Hawking radiation 20m
In this work, we give two proposals regarding the status of connectivity of entanglement wedges and the associated saturation of mutual information. The first proposal has been given for the scenario before the Page time depicting the fact that at a particular value of the observer's time t_b=t_R (where t_R\ll\beta), the mutual information I(R_+:R_-) vanishes representing the disconnected phase of the radiation entanglement wedge. We argue that this time is the Hartman-Maldacena time at which the fine-grained entropy of radiation goes as S(R)\sim \log(\beta), where \beta is the inverse of Hawking temperature of the black hole. On the other hand, the second proposal probes the crucial role played by the mutual information of black hole subsystems in obtaining the correct Page curve of radiation.
Speaker: Anirban Roy Chowdhury (S.N.Bose National Centre for Basic Sciences) -
16:30
Non-local Positivity Bounds: islands in Terra Incognita 20m
The requirement of unitarity and causality in UV lead to significant constraints on low energy EFT known as positivity bounds. While positivity bounds for local QFT have been derived and used widely, we explore the possibility of a non-local UV completion to the low energy EFT. The non-local UV amplitude we propose has the exponential form. We show some of the examples explicitly that satisfy full unitarity and causality, but they are not polynomially bounded. We introduce the dispersion relation that relates low energy EFT and its non-local UV completion. It is found that the resulting bounds can have an overlap with standard local positivity bounds making it not possible to decide whether the given EFT can have only local UV completion. Interestingly, a comparison with causality bounds derived solely from EFT also set a bound for UV theory through dispersion relations.
Speaker: Long-Qi Shao (HangZhou Institute for Advanced Study) -
16:50
Renyi reflected entropy and entanglement wedge cross section with cosmic branes in AdS/BCFT 20m
In this study, we calculate the m−1 correction to the reflected entropy for two adjacent intervals on a half-infinite line within the AdS3/BCFT2 framework, where m is a Renyi index for a canonical purification. We utilize the doubling trick and compute the leading terms in the large central charge expansion of correlation functions in the holographic BCFT. In the corresponding AdS space with an end of the world brane, we analyze the entanglement wedge cross section, the dual counterpart of reflected entropy. This AdS/BCFT setup allows us to explore a richer set of phases in the entanglement wedge cross section. The m−1 correction in the holographic BCFT manifests as modifications in the entanglement wedge cross section induced by cosmic branes. For the adjacent intervals anchored to the boundary of BCFT, we show the duality between the entanglement wedge cross section with the backreaction from a cosmic brane and Renyi reflected entropy at all orders in m−1. Furthermore, by analyzing the entanglement wedge cross section for general adjacent intervals, we provide guidance for an ϵ-expansion of five-point functions in the holographic CFT, where ϵis the rescaled conformal dimension by the central charge.
Speaker: Byoungjoon Ahn (GIST) -
17:10
Entanglement dynamics in 2d HCFTs on the curved background 20m
We will explore the dynamical property of non-equilibrium phenomena induced by two-dimensional holographic conformal field theory (2d holographic CFT) Hamiltonian on the curved spacetime by studying the time dependence of the entanglement entropy and mutual information. Here, holographic CFT is the CFT with the gravity dual. We will start from the boundary and thermofield double states, evolve the systems in Euclidean time with the Hamiltonian on the curved background, and then evolve them in real-time with the same Hamiltonian. We found that the early- and late-time entanglement structure depends on the curved background, while the entanglement growth does not, and is linear. Furthermore, in the gravity dual for the thermofield double state, this entanglement growth is due to the linear growth of the wormhole, while in the one for the boundary state, it is due to the in-falling of the end of the world brane to the black hole. We discussed the low temperature system can be regarded as the dynamical system induced by the multi-joining quenches. We also discussed the effective description of the high temperature system, called line tension picture.
Speaker: Chen Bai (Kavli Institute of Theoretical Sciences, UCAS)
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14:20
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14:20
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17:30
Day 2: Parallel session III Room A120 (TSIMF)
Room A120
TSIMF
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14:20
N=4 SYM on real projective space and analytic conformal bootstrap 30m
I will consider 4d N=4 SYM on real projective space preserving half of supersymmetry and focus on the case where charge conjugation is gauged. The holographic dual of this setup is a Z2 quotient of AdS5xS5 with an O1 orientifold. I will discuss how to use analytic conformal bootstrap techniques to compute all two-point functions of 1/2-BPS operators of arbitrary weights at the leading order in the large central charge expansion.
Speaker: Xi-Nan Zhou (Kavli ITS, University of Chinese Academy of Sciences) -
14:50
Positivity bounds and UV-IR relations in gravity and photon EFT 30m
Unitarity, causality, and Lorentz invariance of the fundamental theory are very constraining assumptions that are capable of building a link between low-energy EFT and its UV completion through the dispersion relations on scattering amplitudes. In this talk, I will consider the EFT of photons (or any other U(1) gauge field) and compare different approaches to obtain bounds on its Wilson coefficients. I will present an analytic derivation of the implications of unitarity (linear and non-linear positivity bounds) and compare these constraints with the requirement of causal propagation of the photon modes around non-trivial backgrounds generated by external sources. I will also discuss UV-IR relations implied by causality in graviton-mediated amplitudes.
*The talk is based on my previous and ongoing work in collaboration with Claudia de Rham and other colleagues from Imperial College London.Speaker: Anna Tokareva (Hangzhou Institute for Advanced Study) -
15:20
Applying Noether's theorem to the pure AdS$_3$ gravity 30m
In this work, we revisit the approach with the covariant phase space formalism for the asymptotic symmetry analysis in the pure AdS3 gravity. We modify the approach to a version which is exactly in the framework of Noether’s theorem. And the key point in the modification is to take a systematical treatment of the boundary effects. In particular, we start from defining the pure AdS3 gravity in Lagrangian formalism, where we adopt proper asymptotic boundary conditions, and we take holographic renormalization in the off-shell level. We then follow Noether’s theorem step by step with a careful treatment of the boundary terms. Following our modified approach, we get the following two results. First, we show that the asymptotic symmetries are indeed symmetries of the pure AdS3 gravity in the sense of Noether’s theorem. Second, we compute the associated charges of the asymptotic symmetries with the equation of Noether charge, which reproduces the same result from the ordinarily used approach with the covariant phase space formalism.
Speaker: Jie-Qiang Wu (Institute of Theoretical Physics, Chinese Academy of sciences) -
15:50
Coffee Break 20m
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16:10
Holographic Weyl Anomaly in 8d from General Higher Curvature Gravity 20m
We calculate the holographic central charges for general higher curvature gravity theory dual to eight dimensional CFT. To do this, we first elaborate the general form of Weyl anomaly in 8d CFT and find 11 non-trivial linearly independent curvature combinations, one of which is Euler density and the rest are Weyl invariants, including 7 non-differentiated ones and 3 differentiated ones. The Weyl invariants are constructed as invariant polynomials of curvature tensor and covariant derivatives. We denote $W_{(n)}$ as the Weyl invariant that contains a polynormial term with a minimum of $n$ curvature tensors. Interestingly, since there are a total of 12 Weyl invariants in 8d, our finding means two of them are trivial and expressible as total derivatives. The resulting central charges are expressed in terms of 15 theory-dependent constants. Remarkably, we find that the $W_{(2)}$ invariant corresponds to the $c$-charge that is proportional to $C_T$, while the two $W_{(3)}$'s are related to three-point function parameters of energy-momentum tensor. This suggests a possible connection between the $c$-charges of $W_{(n)}$'s and the $n$-point functions of energy-momentum tensor.
Speaker: Fei-Yu Chen (Tianjin University) -
16:30
Generalized Fefferman-Graham gauge and boundary Weyl structures 20m
In the framework of the AdS/CFT correspondence, the Fefferman-Graham (FG) gauge offers a useful way to express asymptotically anti-de Sitter spaces, allowing a clear identification of their boundary structure. Although, it is well-known that in holographic theories bulk diffeomorphisms imply Weyl invariance of the dual field theory, choosing a conformal representative for the boundary metric in the FG gauge breaks explicitly this symmetry. Recent developments have shown that it is possible to generalize the FG gauge to restore boundary Weyl invariance. In this talk, we focus on three-dimensional AdS gravity and explore the implications of a boundary Weyl structure by utilizing the generalized Fefferman-Graham (gFG) frame introduced by Grumiller and Riegler in 2016. By extending the holographic renormalization scheme to incorporate Weyl covariant quantities, we construct the quantum-generating functional, extract the holographic stress tensor, compute the Weyl anomaly, and introduce a novel holographic current associated with the boundary Weyl connection. We will briefly comment on an explicit application of this formalism to accelerating black holes.
Speaker: Gabriel Arenas-Henriquez (Tsinghua University) -
16:50
Holographic dual of TTbar BCFT 20m
We consider two types of $T\bar T$ deformed Boundary Conformal Field Theory (BCFT) and propose their holographic duals. The first type, which we refer to as Type A, deforms the boundary of the BCFT using the $T\bar T$ operator. The second type, referred to as Type B, leaves the boundary of the BCFT undeformed. We compute boundary entropy in Type A to show the boundary deformation and compute the entanglement entropy (EE) and Renyi entropy in Type B to provide evidence. Additionally, we generalize the duality to BTZ black hole case and compute the energy spectrum. This further supports the duality.
Speaker: Fei-Yu Deng (Fudan university) -
17:10
Spinodal slowing down and scaling in a holographic model 20m
The dynamics of first-order phase transitions in strongly coupled systems are relevant in a variety of systems, from heavy ion collisions to the early universe. Holographic theories can be used to model these systems, with fluctuations usually suppressed. In this case the system can come close to a spinodal point where theory and experiments indicate that the the behaviour should be similar to a critical point of a second-order phase transition. We study this question using a simple holographic model and confirm that there is critical slowing down and scaling behaviour close to the spinodal point, with precise quantitative estimates. In addition, we determine the start of the scaling regime for the breakdown of quasistatic evolution when the temperature of a thermal bath is slowly decreased across the transition. We also extend the analysis to the dynamics of second-order phase transitions and strong crossovers.
Speaker: Mikel Sanchez Garitaonandia (CPHT, Ecole Polytechnique)
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14:20
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18:10
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20:00
Banquet 1h 50m Sanya Jinsha Seaview Hotel
Sanya Jinsha Seaview Hotel
Sanya Jinsha Seaview Hotel, 159MalingStreet, Sanya, HainanSanya Jinsha Seaview Hotel, 159MalingStreet, Sanya, Hainan.
Please follow the arrangements of organizers
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09:00
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12:20
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09:00
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12:30
Day3 Main venue: Morning Session¶ Room A211 (TSIMF)
Room A211
TSIMF
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09:00
On the open string pair production in Type II superstring theories 40m
In this talk, I will report the progress made on the open string pair production, like the Schwinger pair production in QED, for a system of two Dp-branes placed parallel and with either carrying an electric field in Type II string theories. We explain the physics behind the pair production enhancement when a particular magnetic flux is also applied. In addition, we will discuss the relation between the stringy computed pair production rate and the relevant one computed in QED along with the underlying implications.
Speaker: Jian-Xin Lu (USTC) -
09:40
Holography and Pseudospectra 40m
Quasinormal modes play a major role in the applications of gauge/gravity duality. They arise as eigenvalues of non-normal differential operators. It turns out that they are affected by spectral instability: small perturbations can change the eigenvalues by large amounts. Pseudospectra give a quantitative measure of the spectral (in)stability of eigenvalues. I will review the theory of pseudospectra and their applications in the gauge/gravity duality.
Speaker: Karl Landsteiner (IFT Madrid) -
10:20
Coffee Break 30m
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10:50
On symmetry breaking in AdS/CMT duality 40m
The symmetry breaking plays an essential role in understanding the novel phenomenon in high-temperature superconductivity. We will present a review on various symmetry breaking in the context of AdS/CMT duality, with a focus on providing all the essential ingredients to simulate the phase diagram of the high-temperature superconductivity.
Speaker: Yi Ling (The institute of High Energy Physics, CAS) -
11:30
Is holographic quark-gluon plasma homogeneous? 30m
The presence of Chern-Simons terms in holographic QCD is required by the global flavor anomaly structure. These Chern-Simons terms may give rise to a spatial instability at nonzero density, known as the Nakamura-Ooguri-Park instability. I demonstrate that this instability is unavoidable in a large class of bottom-up models of QCD anchored to lattice data, and extends to surprisingly high temperatures and low baryon number densities in the quark-gluon plasma phase. The precise range of the instability is however sensitive to the strange quark mass, which is not properly included in these models so far.
Speaker: Matti Jarvinen (APCTP, Pohang) -
12:00
Building up Space-time with BCFT legos 30m
Is it possible to read off the quantum gravity dual of a CFT directly from its operator algebra? In this talk, we present a step-by-step recipe synthesizing results and techniques from conformal bootstrap, topological symmetries, tensor networks, a novel symmetry-preserving real-space renormalization algorithm devised originally in lattice models, and the asymptotics of quantum 6j symbols, thereby providing an answer in the affirmative. Quantum 2D Liouville theory serves as a simple and explicit example, illustrating how the quantum gravitational path integral can be built up from local pieces of BCFT correlation functions, which we call the ``BCFT Legos''. If time allows, we will discuss how the bulk theory derived from TTbar flow of CFTs coincides with the bulk that emerges and how that follows from a general holographic principle that we summarize as symQRG = QG.
Speaker: Ling-Yan Hung (Tsinghua University)
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09:00
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12:30
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14:20
Lunch 1h 50m
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14:20
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18:10
Free discussion/Excursion 3h 50m
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18:10
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20:00
Dinner 1h 50m
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09:00
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12:30
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09:00
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13:00
Day4 Main venue: Morning Session¶ Room A211 (TSIMF)
Room A211
TSIMF
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09:00
Reflected entropy for a two-sided black hole model 40m
The black hole information paradox has been an important problem in quantum gravity. In the study of evaporating black hole, it has been proposed that the holographic map between the semi-classical effective description in bulk and the fundamental description in boundary cannot be isometric. In this work, we would like to study the reflected entropy in an evaporating black hole model through non-isometric holographic map. We assume that the evaporating is slowly enough that it makes sense to ascribe a slowly varying temperature to the Hawking radiation. We then introduce a two-sided black hole model to canonically purify the semi-classical state. The holographic map to the fundamental description is non-isometric and defined by a Haar random unitary matrix. We show that the entanglement entropy of the radiation in the model matches the result read from the quantum extremal surface formula and agrees with the Page curve. Furthermore, we study the reflected entropies between different regions, including the one between the black holes on different sides, the one between the radiations distributed symmetrically but disconnectedly, and the one between the black hole and the radiation on single side. Our results are consistent with the existing ones based on the effective descriptions.
Speaker: Bin Chen (Ningbo University) -
09:40
Approaches to Discrete Holography 40m
TBA
Speaker: René Meyer (Julius-Maximilians-Universität Würzburg) -
10:20
Coffee Break 30m
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10:50
NODE Neural ODEs for magnetic holographic QCD phase diagram 30m
The QCD phase diagram is essential for understanding strongly interacting matter under extreme conditions, with important implications for cosmology, neutron stars, and heavy-ion experiments. We present a novel holographic QCD model utilizing neural ordinary differential equations (ODEs) to map the QCD phase diagram under magnetic field $B$, baryon chemical potential $\mu_B$, and temperature $T$. By solving the inverse problem of constructing the theory from Lattice QCD data, we find an unprecedented rich phase structure at finite $B$. Particularly, it uncovers the existence of multiple critical endpoints (CEPs) at strong magnetic fields. For example, under $B = 1.618 \, \mathrm{GeV}^2$, there are two CEPs locating at ($T_C = 87.3 \, \mathrm{MeV}, \, \mu_C = 115.9 \, \mathrm{MeV}$) and ($T_C = 78.9 \, \mathrm{MeV}, \, \mu_C = 244.0 \, \mathrm{MeV}$). Surprisingly, the critical exponents vary based on the CEP’s location. Our findings significantly enhance our understanding of the QCD phase structure and provide concrete predictions for validation at upcoming facilities like FAIR, JPARC-HI, and NICA.
Speaker: Song He (Ningbo University) -
11:20
New understanding on the ''RT'' surfaces for timelike intervals 30m
In this talk I will give a new interpretation for the bulk extremal surface homologous to a boundary time-like interval, as the gravitational anomalous part of an entanglement entropy. This entanglement entropy is exactly the one associated to the space-like interval that shares the same causal development with the time-like one.
Speaker: Qiang Wen (Southeast University) -
11:50
Simulate holographic entanglement entropy and correlation function in hyperbolic lattices 30m
This talk will report an experimental simulation of bulk entanglement entropy (BEE) and boundary-boundary correlation function (BBCF) of scalar fields in two types of hyperbolic lattices, serving as the discretized regularizations of spatial geometries of pure AdS2+1 spacetime and AdS2+1 black hole, respectively. We experimentally confirm that BEE exhibits universal logarithmic scaling with the subsystem size, following the well-known Ryu-Takayanagi (RT) formula, while BBCF displays an exponential law dependence on the boundary separation, the scaling dimension of which conforms to the Klebanov-Witten (KW) relation. This heuristic experimental effort opens a new avenue for in-depth investigations on the gravity/gauge duality and the extensive exploration of quantum-gravity-inspired phenomena in classical systems.
Speaker: Run-Qiu Yang (Tianjin University)
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09:00
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12:20
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14:20
Lunch 2h
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14:20
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18:10
Day 4: Parallel session I Room A211 (TSIMF)
Room A211
TSIMF
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14:20
Pion Condensation and Pion Star from Holographic QCD 30m
The properties of QCD matter at finite isospin densities are investigated employing holographic hard-wall and soft-wall AdS/QCD models. It is confirmed that at high enough isospin densities, charged pions start to condense and the pion superfluid phase appears in the system. It is shown that the chiral condensate and the pion condensate can be transformed to each other and form a `chiral circle' in the superfluid phase. We derived the Equation of State (EoS) for pionic matter, calculated the normalized trace anomaly $\Delta$ and $(\epsilon-3p)/m_\pi^4$, and analyzed the sound speed and adiabatic index. Additionally, we provided data on the mass-radius relation and tidal deformability of pion stars. The results indicate that the holographic models align well with lattice QCD concerning isospin density, axial-vector condensation, EoS, and trace anomaly, though discrepancies in sound speed and adiabatic index emerge at higher isospin chemical potentials. The holographic models closely match those from chiral perturbation theory ($\chi$PT), suggesting that they can be considered as five-dimensional description of $\chi$PT.
Speaker: Yi-Dian Chen (Hangzhou Normal University) -
14:50
Quantum Corrected AdS/CFT Correspondence at Low Temperatures and Its Applications 30m
A large class of black holes have a near-horizon AdS_2 throat region. Using the recent progress on the nearly AdS_2 Jackiw-Teitelboim gravity theory, we can study the quantum gravity effects of the near-horizon AdS_2 region and then lift them to higher-dimensional black holes. It turns out these apparently trivial effects of quantum gravity can play crucial roles in the near-extremal AdS/CFT correspondence. In this talk, we will discuss the mechanism of AdS_2 quantum effects embedded in higher-dimensional AdS spaces and the quantum-corrected AdS/CFT correspondence at low temperatures. As applications, we discuss how this new approach resolves various problems, including quantum-corrected holographic strange metal and quantum-corrected fluid/gravity correspondence. Most importantly, quantum gravity effects provide new insights into the formidable long-standing Yang-Mills confinement problem. This talk is based on my recent and upcoming papers with collaborators.
Speaker: Jun Nian (University of Chinese Academy of Sciences) -
15:20
Holographic Bound of Casimir Effect 30m
Casimir effect is a novel boundary quantum effect that originates from the changes of vacuum energy due to the boundary. Is there a fundamental bound of Casimir effect? This talk tries to address this critical question. Inspired by the KSS bound, we propose that the holographic theory imposes a universal bound of Casimir effect. We verify this universal bound by free BCFTs, and provide evidence that it applies to a general class of QFTs, not limited to BCFTs.
Speaker: Rong-Xin Miao (Sun Yat-sen University) -
15:50
Coffee Break 30m
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16:20
Hydrodynamics at Causal Boundaries: 3d Example 30m
We study three-dimensional gravity on a spacetime bounded by a generic two-dimensional causal surface, constructing the solution phase space specified by four generic functions over the causal boundary. We discuss the symplectic form, boundary charges, and their algebra, providing a fluid description at the causal boundary. This description covers an extension of known asymptotic hydrodynamics for 3d AdS or flat space. Additionally, we develop a framework revealing the intrinsic conserved stress tensor and current at the null infinity of 3d asymptotically flat spacetime, conjugate to the degenerate metric and Ehresmann connection of the boundary null geometry. Their conservation reproduces Bondi-mass and angular momentum equations with a specified torsional affine connection. Our results enhance 3d flat holography, showing a flat fluid/gravity correspondence and yielding a Schwarzian action at null infinity, aligning with codimension 2 holography of 3d flat spacetimes.
Speaker: Hamed Adami (Shanghai Institute for Mathematics and Interdisciplinary Sciences) -
16:50
Fluid/Gravity Duality for Viscoelastic Crystals 20m
In the absence of dislocations, the hydrodynamics of two-dimensional crystals can be accounted for by considering a set of 1-form global symmetries. In thermal equilibrium, the holographic dual to such a crystal is an AdS black brane charged under 2-form gauge fields. By extending the fluid-gravity correspondence to such backgrounds we obtain both dissipative and non-dissipative transport coefficients. We also consider the spectrum of hydrodynamical modes and find instabilities for a certain range of our theory’s parameters.
Speaker: Andre Oliveira Pinheiro (Heriot-Watt University) -
17:10
Strange Metal from SYK-rised Vector Model 20m
In this talk, I will present a model describing the spatially random coupling between a fermi surface and a bosonic vector field. Its transport properties will be shown to illustrate if spatial randomness could be the mechanism under the strange metals.
Speaker: Yi-Li Wang (Hanyang University) -
17:30
The effect of charm quark on chiral phase transition in holographic QCD 20m
Studying the thermal QCD phase transition and the critical endpoint is crucial for understanding the hot environment relevant to the initial stage of heavy-ion collisions and the early universe. The nature of the QCD chiral phase transition in the limit of massless quarks has been a longstanding, open problem. The discrepancy between the lattice QCD estimation and the effective model results appears for the order of the chiral phase transition in the case of a multi-flavor system. In this talk, We present a study on the thermal chiral phase transition in a four-quark flavor system using the soft-wall holographic QCD model. Our study reveals that in the massless limit, the thermal chiral phase transition is of the second order in the four-quark flavor system. However, in the case of the massive charm quark and the massless light and strange quarks, the order of the phase transition changes to the first order. We also map the order of the phase transition on a phase diagram in the quark mass plane where the light- and strange-quark masses degenerate but differ from the value of the charm quark mass. Finally, we address the critical exponents related to the chiral phase transition.
Speaker: Hiwa Ahmed (University of Chinese Academy of Scineces) -
17:50
QCD phase diagram from a 5-D holographic hardwall model 20m
In this presentation, we will discuss the QCD phase diagram at finite temperature and baryon chemical potential obtained from an AdS/QCD hardwall model. The novelty of our work is to obtain solutions that represent the strongly interacting nuclear matter by applying boundary conditions derived from NJL and Van der Waals-type equations of state. Further, we investigate the possibility of baryonic condensates using the ideas of holographic superconductors.
Speaker: Akash Singh (IISER Mohali (India))
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14:20
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14:20
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18:10
Day 4: Parallel session II Room A110 (TSIMF)
Room A110
TSIMF
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14:20
Vacuum Bubble tunneling 30m
We study the vacuum decay and the bubble nucleation in the anti-de Sitter black holes. In the bubble nucleation spacetime, the interior and the exterior of the bubble wall are described by two anti-de Sitter black hole spacetimes with different cosmological constants. We calculate the Euclidean action of the bubble nucleation spacetime and give the numerical results of the tunneling rates for different cases. It is shown that the black hole can act as a source of inhomogeneities and catalyze the vacuum decay and the bubble nucleation in the anti-de Sitter spacetime. For the RNAdS black holes, the tunneling rate to the final RNAdS black hole with the minimum critical mass is the highest among all the possible tunneling channels.
Speaker: Jin Wang (Wenzhou Institute and State University of New York at Stony Brook) -
14:50
Non-Hermitian RG Flows 30m
We study holographic theories featuring a non-Hermitian inhomogeneous scalar deformation. We find phases where a purely imaginary current breaks PT-symmetry spontaneously. These PT-broken phases flow in the IR towards a pseudo-Hermitian conformal fixed point realizing PT-symmetry restoration at the end of the RG flow.
Speaker: Daniel Arean (Instituto de Física Teórica. Universidad Autónoma de Madrid) -
15:20
Holographic Modeling and Realization of Topological Semimetal Coexistence States 30m
We present holographic models exhibiting the coexistence state of topological semimetals, thereby providing us with a valuable tool to investigate the system's behaviour in the strongly coupled regime. A number of distinct bulk solutions, each exhibiting a different infrared (IR) behaviour, have been identified, and these correspond to different types of boundary state. These states encompass distinct topological phases, critical phases and topological trivial phases. Phase diagrams are plotted that exhibit qualitative similarity to the one obtained in the weak coupling limit. The anomalous Hall conductivity, which serves as an order parameter, and the free energy are calculated. The latter demonstrates the continuity of the topological phase transitions within the system. This work elucidates the similarities and differences between a topological system in the weak and strong coupling regimes, thereby paving the way for further experimental observations.
Speaker: Xuan-Ting Ji (China Agricultural University) -
15:50
Coffee Break 20m
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16:10
Implications of f(Q) Gravity on Cosmological Parameters 20m
In this presentation, we investigate the impact of f(Q) gravity on key cosmological parameters, extending beyond the framework of General Relativity (GR) by incorporating non-metricity. We analyze the modified Friedmann equations derived from this theory to understand the evolution of the Hubble parameter, energy density, pressure, and the equation of state parameter. Our findings suggest that f(Q) gravity shows promise as an alternative to GR, particularly in explaining the accelerated expansion of the universe. By solving these modified Friedmann equations, we present a comprehensive set of differential equations that describe the cosmological evolution within the FLRW model under f(Q) gravity. These results pave the way for further exploration of modified gravity theories and their potential to address unresolved challenges in cosmology.
Speaker: Chaymae Karam (Mohammed V University of Rabat, Faculty of Sciences (High Energy Physics Team - Modeling and Simulation)) -
16:30
Building holographic code from the boundary 20m
Holographic quantum error-correcting code, the quantum-information structure hypothesized for the AdS/CFT correspondence, has being attracting increasing attention in new directions interrelating the studies of quantum gravity and quantum simulation. In this work, we initiate a novel approach for building holographic code that can be generally applied in potentially broad and interdisciplinary contexts. Our approach takes an "opposite" route to the conventional paradigm that is based on bulk tensor-networks. As illustrated in an exact model, we start from scalable descriptions of boundary qudits which can guide succinct quantum-circuit simulations, and rigorously show how the bulk qudits and the encoding structure emerge from boundary entanglement patterns. By investigating the entanglement patterns, we systematically unfold the hypothetical structure for bulk reconstruction and the details of the Ryu-Takayanagi formula in the formalism of operator-algebra quantum error correction, demonstrating desired properties that are not yet proved in the established models. Our work might offer a fresh perspective for the study of holographic code.
Speaker: Wei Wang (SJTU Tsung-Dao Lee Institute) -
16:50
The upper bound of holographic n-partite information 20m
To analyze the holographic multipartite entanglement structure, we study the upper bound for holographic n-partite information I_n that n-1 fixed boundary subregions A,B,... participate together with an arbitrary region E for n=3,4,5. In all cases that we study, we could find regions E that make I_n tends to the information upper bound. For n=3, we prove that the upper bound of conditional mutual information I(A:B|E) is given by a quantity which we name the entanglement of holographic purification EoHP(A:B). For n=4,5, we find that the upper bound of I_n is finite in CFT_{1+1} but has UV divergences in higher dimensional CFT, which reveals a fundamental difference in the entanglement structure between CFT_{1+1} and higher dimensional CFTs. Moreover, the relationship between the convexity of regions A,B,... and multipartite entanglement they participate is also revealed in higher dimensional case. We argue that (I_n) fully accounts for multipartite entanglement in these upper bound critical points, in contrast to usual cases where I_n is not a perfect measure for multipartite entanglement. These results suggest that fewer-partite entanglement in holography fully emerges from more-partite entanglement, and any n-1 small convex regions are fully n-partite entangling in general.
Speaker: Xin-Xiang Ju (University of Chinese Academy of Sciences) -
17:10
Disordered charged horizons 20m
We present a bottom-up model for the holographic dual of 2D and 3D strongly interacting systems with a disordered chemical potential along one spatial direction. On the gravity side, we introduce disorder through a space-dependent source for a U(1) gauge field sampled from a Gaussian white noise distribution; we ensure the disorder is Harris-relevant. At high temperatures, we observe disordered charged horizons. We find distinct behaviours for the two cases after lowering the temperature while remaining within the disordered regime. In the AdS_3 scenario, contrary to the expectation from the Harris criterion, inhomogeneities at the horizon die off as the temperature decreases, leading to the clean IR fixed point. Conversely, in the AdS_4 case, we propose that the dual theory flows to an inhomogeneous IR fixed point with finite conductivity. The average geometry of the inhomogeneous IR coincides with the clean fixed point.
Speaker: Pau Garcia Romeu (Instituto de Física Teórica (UAM-CSIC)) -
17:30
Thermodynamics, magnetic properties, and global U(1) symmetry breaking of the S-type Gubser-Rocha model 20m
We study an explicit formula for the thermodynamic potential of the AdS dyonic black brane solution with an axio-dilaton hair, which was discovered in an extension of the (3+1)d Gubser-Rocha model enjoying S-duality. From the thermodynamic potential, we compute the magnetization and the magnetic susceptibilities of the dyonic solution. The result of the magnetization is negative implying that the system is diamagnetic. Subsequently, we consider a specific neutral limit of the dyonic solution. In this setup, we find that the system exhibits spontaneous breaking of a global U(1) symmetry. The order parameter is given by a complex operator which is dual to the axio-dilaton field in the bulk. Interestingly, the system has a finite Hall conductivity even in the absence of the external magnetic field, and it is related to the phase of the complex operator.
Speaker: Shuta Ishigaki (Shanghai U.) -
17:50
Thermodynamics and quantum critical magnetocaloric effect in Einstein-Maxwell-Chern-Simons theory 20m
Thermodynamics of black holes offers a promising avenue for exploring the quantum nature of black holes and quantum gravity. In this work, we investigate the thermodynamic properties of dyonic black holes in the five-dimensional Einstein-Maxwell-Chern-Simons theory, obtained from IIB supergravity. We demonstrate that the standard form of the first law of thermodynamics is inconsistent with the quantum statistical relation widely adopted in black hole physics. By employing the on-shell variation of the Euclidean action and the Iyer-Wald formalism, we resolve this discrepancy and derive both the standard form of the first law and Smarr formula for the dyonic black holes. Furthermore, our findings are corroborated by numerical tests and are consistent with general hydrodynamic expectations. We will also discuss the quantum critical magnetocaloric effect (MCE) in this holographic model, where we show the existence of quantum criticality, obtain its universality class, and discuss the MCE characterized by the Gruneisen parameter.
Speaker: Jun-Kun Zhao (Institute of Theoretical Physics, Chinese Academy of Sciences)
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14:20
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14:20
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18:10
Day 4: Parallel session III Room A120 (TSIMF)
Room A120
TSIMF
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14:20
Non-extremal Island in de Sitter Gravity 30m
In this talk, I will present our recent approach to calculating the entanglement entropy for quantum field theories coupled to de Sitter (dS) gravity along a timelike boundary. Traditional techniques, such as the island formula—originally developed for non-gravitational systems coupled to AdS gravity—encounter significant challenges when extended to a de Sitter gravitational setting, where no physically consistent extremal island solution emerges. We propose a doubly holographic framework to address these limitations by embedding a dS$_2$ braneworld within an AdS$_3$ bulk spacetime. Thanks to the higher-dimensional holographic duality, this configuration allows us to circumvent the constraints of the island formula. We show that the correct recipe for calculating entanglement entropy in the presence of dS gravity involves the non-extremal island, whose boundary is instead defined at the edge of the dS gravitational region. Our findings indicate that, during the island phase, the entanglement wedge of the non-gravitational bath encompasses the entire dS gravitational region. Using the second variation formula, we further show that the existence of a locally minimal surface anchored on the gravitational brane is intrinsically linked to the extrinsic curvature of the brane.
Speaker: Shan-Ming Ruan (Vrije Universiteit Brussel) -
14:50
Regularity of black holes in non-perturbative quantum gravity 30m
In my talk I will discuss subtleties of constructing Black Hole solutions in higher and infinite derivative gravity theories. Special attention will be paid to questions why infinite derivatives are important and how to deal with infinite derivative equations. A connection between absence (or presence) of a singularity and a structure of a non-perturbative graviton propagator will be explained highlighting that non-singular black holes are favored.
Speaker: Alexey Koshelev (ShanghaiTech University) -
15:20
Holographic spin alignment for vector mesons 30m
We develop a general framework for studying the spin alignment ρ00 for flavorless vector mesons by using the gauge/gravity duality. Focusing on the dilepton production through vector meson decay, we derive the relation between production rates at each spin channel and meson’s spectral function in a thermal medium, which can be evaluated by holographic models for a strongly coupled system. As examples, we study ρ00 for J/ψ and ϕ mesons, induced by the relative motion to a thermal background, within the soft-wall model. Spectral functions for J=ψ at T =150 MeV have significant resonance peaks, indicating that c−c¯ can exist as quasistable J/ψ mesons. However, no significant peaks for the ϕ meson are observed at the same temperature, implying that ϕ mesons are melting down at this temperature and spectral functions are interpreted as probabilities of unstable s−s¯ pairs. These pairs are related to free-streaming ϕ mesons by an instantaneous freeze-out assumption, which is performed by sandwiching the in-medium spectral function between the meson’s free-streaming propagators. Then only states with invariant masses closing to the meson’s vacuum mass survive during the freeze-out stage and contribute to final results. We show that ρ00 in the helicity frame for J/ψ and ϕ mesons have positive and negative deviations from 1=3 at T = 150 MeV, respectively, which consequently leads to different properties for their global spin alignments. In addition, we delve into the J/ψ meson’s spectral function and spin parameters (λθ, λφ, λθφ) for different cases, assessing their response to variations in magnetic feld strength, momentum, and temperature.
Speaker: Yan-Qing Zhao (HaiNan Normal University) -
15:50
Coffee Break 20m
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16:10
Holography from Conformal Field Theory 30m
In this talk we explain how collective field theory provides a constructive approach to the AdS/CFT correspondence. In particular, we explain how the redundancy present in the collective field theory is directly responsible for the holographic character of the gravitational description.
Speaker: Robert de Mello Koch (Huzhou University) -
16:40
Construction of Superconducting dome and Quantum Critical Region 30m
We investigate an extended model of holographic superconductor by a nonlinear electrodynamic interaction coupled to a complex scalar field. This non-linear interaction term can make a quantum phase transition at zero temperature with finite charge carrier density. By solving full equations of motion, we can construct various shapes of the superconducting phase in the phase diagram. With a specific choice of interaction coefficients, we can construct a phase diagram with a superconducting dome. Also, we find a new geometric solution inside the superconducting dome, which turns out to be a Lifshitz-type geometry. We develop our model using machine learning technique to find out the mass function of the scalar field. By using physics informed neural network method, we find mass function for the experimental data of the high Tc superconductors.
Speaker: Yunseok Seo (Kookmin University) -
17:10
Holographic supersolids--non-equilibrium phase transition and topological defects formation 20m
Since the establishment of holographic superfluid model, extensive reearches have been worked about zero or finite temperature systems in various aspects. However, few studies touched the phenomenon about supresolids and the phase transition of superfluid-supersolid, as more and more experiments are comfirming the existence of supersolid phase in superfuid systems. To fill the gap, we try to study supersolid related phenomena by using original holographic superfluid model. Instead of finding ground supersolid state, we mainly focus on the supersolid state that emerges from non-equilibrium system. Especially, we will introduce an non-equilibrium phase transition with spacetime supersolids formation and a dynamical process of transient supersolids with topological defects formation.
Speaker: Peng Yang (Shanghai Jiao Tong university) -
17:30
DeepCosmo: A New Method of Neural Network Trained with Tetrad-Based Riemann Curvature Tensor Calculation for Solving Einstein Field Equations in AdS/CFT Duality 20m
Traditional numerical methods face unprecedented challenges when solving complex gravitational problems, especially in the computation of black hole metric in AdS/CFT duality. This paper proposes an innovative approach — DeepCosmo, which combines the method of computing curvature tensors using orthonormal rigid tetrad to train neural networks, exploring a new path for efficiently obtaining accurate solutions to highly nonlinear Einstein’s field equations through machine learning. Compared to existing research that is limited in computing Christoffel symbols, DeepCosmo utilizes Ricci rotation coefficients, connection 1-forms, and Cartan's second structural equation to obtain the Riemann tensor. This not only reduces computational complexity of AdS/CFT duality but also significantly improves training and operational efficiency while offering better physical intuition, accelerating research in the field of AdS/CFT duality. This paper presents multiple variants of DeepCosmo based on deep neural networks, exploring the fitting effects of different DeepCosmo variants. By employing various solutions of Einstein’s field equations, such as the Schwarzschild vacuum solution, and the Reissner-Nordstrom solution, the effectiveness of the DeepCosmo method is verified from multiple perspectives.
Speaker: Chenqingshui Huang (Central China Normal University Wollongong Joint Institute) -
17:50
On AdS$_3$/ICFT$_2$ with a dynamical scalar field located on the brane 20m
We exploit the holographic duality to study the system of a one-dimensional interface contacting two semi-infinite two-dimensional CFTs. Central to our investigation is the introduction of a dynamical scalar field located on the bulk interface brane which breaks the scaling symmetry of the dual interface field theory, along with its consequential backreaction on the system. We define an interface entropy from holographic entanglement entropy, to construct a $g$-function. At zero temperature we construct several illustrative examples and consistently observe that the $g$-theorem is always satisfied. These examples also reveal distinct features of the interface entropy that are intricately linked to the scalar potential profiles. At finite temperature we find that the dynamical scalar field enables the bulk theory to have new configurations which would be infeasible solely with a tension term on the interface brane.
Speaker: Chuan-Yi Wang (Beihang University)
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14:20
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18:10
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20:00
Dinner 1h 50m
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09:00
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13:00
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12:20
Day5 Main venue: Morning Session¶ Room A211 (TSIMF)
Room A211
TSIMF
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09:00
Holographic scattering and non-minimal RT surfaces 40m
In the AdS/CFT correspondence, the causal structure of the bulk AdS spacetime is tied to entanglement in the dual CFT. This relationship is captured by the connected wedge theorem, which states that a bulk scattering process implies the existence of O(1/G) entanglement between associated boundary subregions. In this paper, we study the connected wedge theorem in two three-dimensional asymptotically-AdS spacetimes: the conical defect and BTZ black hole geometries. In these settings, we find that bulk scattering processes require not just large entanglement, but also additional restrictions related to candidate RT surfaces which are non-minimal. We argue these extra relationships imply a certain CFT entanglement structure involving internal degrees of freedom. Because bulk scattering relies on sub-AdS scale physics, this supports the idea that sub-AdS scale locality emerges from internal degrees of freedom.
Speaker: Robert Myers (Perimeter Institute) -
09:40
Holographic mean field theory and Kondo lattice Problem 40m
The usual AdS/CMT is based on the equivalence of the quantum critical point and the black hole. However, at the critical point, there is no scale, therefore we can not encode any shape or scale that characterizes the material and therefore we can not answer following question: About what material we are talking about? So we need to extend the AdS/CMT by introducing one or a few scale to make AdS/CMT an interesting condensed matter theory. We answer this question by following the Landau-Ginzberg paradigm in the context of the Holography. Namely, we study the effects of the symmetry breaking to the fermion dispersion relation. Interestingly, we found all the interesting features of the topology material is found in this way. Based on this formalism we discuss two applications: 1) Topology of the quantum material and 2) Kondo lattice.
Speaker: Sang-Jin Sin (Hanyang U.) -
10:20
Entanglement in timelike region and sum rule 30m
We usually investigate the entanglement between different spacelike regions. From the perspective of quantum field theory, it is natural to generalize the concept of spacelike entanglement to timelike entanglement. This can be achieved through the analytical continuation of correlation functions of twist operators. In this approach, we have unified the concepts of timelike and spacelike entanglement. Moreover, we also discovered that the timelike entanglement entropy has an interesting sum rule that connects with the spacelike entanglement entropy. This sum rule holds true for many examples, both in two-dimensional and higher-dimensional conformal field theories (CFTs). We will also discuss the possibility of generalizing timelike entanglement to other entanglement measures, such as negativity. Timelike entanglement appears to be connected with complex geometry and the complex Ryu-Takayanagi surface.
Speaker: Wu-Zhong Guo (Huazhong University of Science and Technology) -
10:50
Coffee Break 30m
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11:20
Pole collisions and effective actions in holographic theories 30m
I will discuss the convergence properties of hydrodynamic modes from holographic pole collision. I will focus on a particular holographic system with an infrared semi-local quantum liquid phase, and explain the different physical consequences due to two types of lowest non-hydrodynamic modes. Finally, I will describe the Schwinger-Keyldysh effective actions incorporating these non-hydro modes.
Speaker: Yan Liu (Beihang University) -
11:50
Quantum simulation of Unruh effect in trapped ion 30m
In this talk, we will introduced our recent experiment about quantum simulation of Unruh effect in trapped ion. There are two topics: 1) how the superposition of trajectories affects the Unruh effect and particle creation from vacuum fluctuations; 2)observation of timelike Unruh effect, and verification that the Rindler spacetime is the fastest scrambler in nature pointed out by Yasuhiro Sekinoab and L. Susskind (“ Fast scramblers”, JHEP 10 (2008) 065).
Speaker: Ze-Hua Tian (Hangzhou Normal University)
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09:00
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12:20
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14:20
Lunch 2h
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14:20
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18:20
Day5 Main venue: Afternoon Session¶ Room A211 (TSIMF)
Room A211
TSIMF
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14:20
Linear dynamical stability and the laws of thermodynamics 40m
I will show that the dynamical stability under linear perturbations of interacting systems in the hydrodynamic regime follows from the first and the second laws of thermodynamics. The argument extends to systems with spontaneously or softly broken symmetries and in the presence of magnetic fields.
Speaker: Blaise Goutéraux (Ecole Polytechnique, Institut Polytechnique de Paris) -
15:00
Proper Effective Temperature and Order Parameters in Relativistic Non-Equilibrium Steady States 30m
We investigate a spontaneous symmetry breaking of a relativistic (2+1)-dimensional defect moving at a constant velocity in a (3+1)-dimensional heat bath using the D3-D5 model of the gauge/gravity duality. We find that the dependence of the order parameter on the heat-bath temperature and the defect velocity is uniquely expressed through a single variable, the proper effective temperature, for the moving defect. Our results suggest that the proper effective temperature is an essential parameter for a class of relativistic non-equilibrium steady states.
Speaker: Shin Nakamura (Chuo University) -
15:30
Black Holes: Internal Structures and Holographic Topological Properties 20m
The interiors of black holes remain worthy of exploration. The dynamic evolution of spacetime from horizon to singularity can exhibit intriguing behaviors. In this talk, I will introduce two works on black hole interiors. In the first work, we extend our analysis to stationary black holes—specifically, 3D hairy rotating black holes. We find that the inner horizons are always destroyed by scalar hairs and the collapse of Einstein-Rosen bridge is always present. The singularities will evolve into Kasner singularities with possible inversion. In the second work, we examine the interiors during the topological phase transition in two holographic semimetal models. The interiors exhibit a “topological invariance” behavior, likely reflecting the topological nature of the semimetals.
Speaker: Ling-Long Gao (Beihang University) -
15:50
Disordered quantum critical fixed points from holography 20m
Using holographic duality, we present an analytically controlled theory of quantum critical points without quasiparticles, at finite disorder and finite charge density. These fixed points are obtained by perturbing a disorder-free quantum critical point with relevant disorder whose operator dimension is perturbatively close to Harris marginal. We analyze these fixed points both using field theoretic arguments, and by solving the bulk equations of motion in holography. We calculate the critical exponents of the IR theory, together with thermoelectric transport coefficients. Our predictions for the critical exponents of the disordered fixed point are consistent with previous work, both in holographic and nonholograpic models.
Speaker: Xiao-Yang Huang (University of Colorado, Boulder) -
16:10
Coffee Break 30m
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16:40
Uncovering thermodynamic origin of counterflow and coflow instabilities in miscible binary superfluids 20m
In this paper, we explore instabilities in binary superfluids with a nonvanishing relative superflow, particularly focusing on counterflow and coflow instabilities. We extend recent results on the thermodynamic origin of finite superflow instabilities in single-component superfluids to binary systems and derive a criterion for the onset of instability through a hydrodynamic analysis. To verify this result, we utilize both the Gross-Pitaevskii equation (GPE) for weakly interacting Bose-Einstein condensates (BEC) and a holographic binary superfluid model, which naturally incorporates strong coupling, finite temperature, and dissipation. We find that the counterflow and coflow instabilities in binary superfluids are all essentially thermodynamic. Except the one due to order competing via global thermodynamic instability, the others are caused by an eigenvalue of the free energy Hessian diverging and changing sign. We also observe that the critical velocities of these instabilities follow a general scaling law related to the interaction strength between superfluid components. The nonlinear stages of the instabilities are also studied by full time evolution, where vortex dynamics is found to play a significant role, resulting in the reduction of superfluid velocity back to a stable phase.
Speaker: Yu-Ping An (Institute of Theoretical Physics, Chinese Academy of Sciences) -
17:00
A Holographic Study of Multi-Magnetic Field Magnetohydrodynamics 20m
We studied magnetohydrodynamics through the perspective of holography, where the gravity side is represented by a 5-dimensional model of three magnetic fields, with each field occupying distinct spatial coordinates and orthogonal to one another. The CFT side describes non-conformal fluids but becomes conformal when considering only the first-order part. We constructed the constitutive relations for magnetohydrodynamics and found that some transport coefficients become matrices in the multi-charge scenario. All the first-order transport coefficients can be derived using Kubo formulae.
Speaker: Yan-Qi Wang (Tianjin University) -
17:20
Shear transport in far-from-equilibrium isotropization of supersymmetric Yang-Mills plasma 20m
We holographically study the far-from-equilibrium isotropization dynamics of the strongly coupled $\mathcal{N}=4$ supersymmetric Yang-Mills plasma. The dual gravitational background is driven to be out of equilibrium and anisotropic by a time-dependent change in boundary conditions. At late times, the system relaxes and asymptotically approaches a static configuration. The large initial energy densities accelerate the isotropization significantly compared to the initial geometry corresponding to the supersymmetric Yang-Mills vacuum. We analyze shear transport during isotropization by directly computing the time-dependent stress tensor, which is now a nonlinear function of the shear rate. The shear viscosity far from equilibrium displays much richer dynamics than its near-equilibrium counterpart. Moreover, we uncover that the equilibrium viscosity-to-entropy ratio at late times depends on the details of the quench function and the initial data, which could be due to a resummation of the hydrodynamic description. In particular, this ratio can be parametrically smaller than the Kovtun-Son-Starinets bound calculated from linear response theory.
Speaker: Shou-Cheng Wang (ITP, CAS) -
17:40
Bayesian Inference of the Critical Endpoint and heavy quarkonium potential energy in flavor-dependent systems from Holographiy QCD 20m
By incorporating the equation of state and baryon number susceptibility from lattice QCD with error bars at zero chemical potential, we developed a Bayesian Inference model within the framework of holographic QCD. This model includes error estimates derived from lattice data. Based on this Bayesian holographic model, we investigated the thermodynamic quantities for the 2-flavor and 2+1-flavor systems. Using Bayesian analysis, we calibrated the parameters and then calculated the critical endpoint (CEP) location for the best-fit results of the 2-flavor and 2+1-flavor systems as ($\mu_B=0.430$ GeV, $T=0.110$ GeV) and ($\mu_B=0.702$ GeV, $T=0.091$ GeV), respectively. We also computed the CEP regions within the 68\% and 95\% confidence intervals in the posterior distribution for both cases. We compared our findings with the possible CEP locations proposed by other theoretical models to verify the validity of our model. Additionally, we employed this model to study the potential energy of heavy quarkonium for the 2-flavor and 2+1-flavor systems using Bayesian analysis, presenting posterior distribution results for the heavy quark potential energy.
Speaker: Li-Qiang Zhu (Central China Normal University) -
18:00
Quantum Corrections to Holographic Strange Metal at Low Temperature 20m
The holographic approach to the strange metal phase relies on extremal AdS4 black holes with important input from their AdS2 throat geometry. Motivated by the current understanding of the role of quantum fluctuations in the throat of the black hole. We model quantum gravity and gauge fluctuations in the throat region by adopting results in JT gravity, effectively leading to quantum corrections for the dual CFT1 Green's function. We use the quantum-corrected Green's function to compute the conductivity for (2+1)-d strange metal and obtain corrections for the DC resistivity and the optical conductivity. The quantum corrections for DC resistivity require higher precision than the current experimental accuracy to be detected in the future. The quantum corrections for optical conductivity provide a plausible explanation for the experimental anomalous power-law behavior detected in various strange metals. We will discuss these aspects in this talk.
Speaker: Xiao-Long Liu (ICTP-AP, UCAS)
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14:20
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18:20
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20:00
Dinner 1h 40m
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09:00
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12:20