This satellite meeting, part of the International Congress on Basic Science (ICBS), will explore recent developments at the interface of gravitational physics, geometric structures, and operator algebras. The event aims to foster collaboration between mathematicians and theoretical physicists working in related fields.
The conference will focus on key topics including:
- Classical and quantum aspects of gravitational theories
- Applications of operator algebras in quantum ffeld theory and quantum gravity
- Holography and emergent geometry
- Symmetries, conserved charges, and boundary structures
- Mathematical structures in gauge and string theories
Date: 2025-09-01 ~ 2025-09-05
地点： R1510, SIMIS
组织者： Hamed Adami ( SIMIS ), Mauricio Romo ( SIMIS )
Speakers:
- Luis Apolo ( 路易斯·阿波罗, BIMSA )
- Gabriel Arenas-Henriquez ( YMSC, Tsinghua )
- Bin Chen ( Ningbo University and Peking University )
- Ricardo Espíndola ( IAS, Tsinghua University )
- Wu-Zhong Guo ( 郭武中, Hua-Zhong U. Sci. Tech. )
- Song He ( 何松, Ningbo University )
- Jiang Long ( Hua-Zhong U. Sci. Tech. )
- Azadeh Maleknejad ( Swansea University )
- René Meyer ( Julius-Maximilians-Universität Würzburg )
- Rongxin Miao ( Zhongshan University, Zhuhai )
- Anton Pribytok ( 安东·普里比托克, BIMSA )
- Laurentiu Rodina ( 劳伦修·罗迪纳, BIMSA )
- Tomasz Smołka ( University of Warsaw )
- Jie-Qiang Wu ( CAS Key Laboratory of Theoretical Physics )
- Yihao Yin ( NUAA, Nanjing )
- Ellis Ye Yuan ( Zhejiang University, Inst. Mod. Phys. )
- Zhifei Zhu ( 朱知非, YMSC, Tsinghua University )
- Hossein Babaei Aghbolagh ( Ningbo University )
Schedule:
| Sep 1 Mon | Sep 2 Tue | Sep 3 Wed | Sep 4 Thu | Sep 5 Fri | |
|---|---|---|---|---|---|
| 10:00-11:00 | L. Apolo | E. Yuan | W. Guo | B. Chen | R. Meyer |
| 11:00-12:00 | A. Pribytok | S. He | T. Smołka | J. Wu | Hossein Babaei Aghbolagh |
| 14:00-15:00 | R. Espíndola | J. Long | Y. Yin | A. Maleknejad | |
| 15:00-16:00 | Z. Zhu | L. Rodina | R. Miao | G. Arenas-Henriquez |
*All time in this webpage refers to Beijing Time (GMT+8).
Program:
2025-09-01
| 10:00-11:00 Luis Apolo ( 路易斯·阿波罗 , BIMSA ) The on-shell action of supergravity & (single-trace) TTbar |
| 11:00-12:00 Anton Pribytok ( 安东·普里比托克 , BIMSA ) Superdeformed CPn model and Order defects We prove that the supersymmetric deformed $\mathbb{CP}^1$ sigma model admits an equivalent description as a generalized Gross-Neveu model. Remarkably we find new Nahm-type conditions, which guarantee renormalizability and supersymmetric invariance. Moreover it provides formalism, which is useful for the study of renormalization properties and particularly for calculation of such observables as $\beta$ and correlation functions. We study the RG flow of the new class and find special UV conformal points from both sides of the new Chiral/Sigma model correspondence. We further explore novel relations of our construction through mirror symmetry and dimensional reductions. We demonstrate its emergence from the four-dimensional TQFT with defects, investigate surface observables and provide the associated spin chain system. |
| 14:00-15:00 Ricardo Espíndola ( IAS, Tsinghua University ) The topology of kinematic space and a two-sided Crofton formula A central challenge in holography is understanding how spacetime emerges from the boundary conformal field theory (CFT). Entanglement provides a geometric perspective through kinematic space—the space of CFT point pairs or bulk minimal cuts—where spacetime geometry is encoded in an integral formula with quantum information meaning: the Crofton formula, a cornerstone of integral geometry. In this talk, I will present recent advances revealing a novel two-sided Crofton formula, which reconstructs wormhole geometries by resolving quantum puzzles. This reveals a deeper organizational principle, leading to the discovery of new topological kinematic spaces with rich topological structure that underlies spacetime emergence. |
| 15:00-16:00 Zhifei Zhu ( 朱知非 , YMSC, Tsinghua University ) Length of closed geodesics on Riemannian manifolds with bounded Ricci curvature In this talk, we show that the length of a shortest closed geodesic on Riemannian manifolds of dimension 4 with diameter D, volume v, and $|Ric|<3$ can be bounded by a function of v and D. In particular, this function can be explicitly computed if the manifold is Einstein. The proof of this result depends on a structural theorem proven by J. Cheeger and A. Naber. This is joint work with N. Wu. |
2025-09-02
| 10:00-11:00 Ellis Ye Yuan ( Zhejiang University, Inst. Mod. Phys. ) Kaluza-Klein AdS Virasoro-Shapiro Amplitudes We bootstrap the first-order correction in the curvature expansion of the Virasoro-Shapiro amplitude in AdS spacetime, for arbitrary Kaluza-Klein charges of external operators. By constructing a universal ansatz based on single-valued multiple polylogarithms as well as an AdSxS formalism, and matching it with the low-lying result, we derive a unified formula in terms of world-sheet integrals. Our result predicts an infinite number of Wilson coefficients that were not available in previous literature. I will also report some ongoing progress on the second-order correction. |
| 11:00-12:00 Song He ( 何松 , Ningbo University ) 待定 |
| 14:00-15:00 Jiang Long ( Hua-Zhong U. Sci. Tech. ) Extrapolating fields to future timelike infinity |
| 15:00-16:00 Laurentiu Rodina ( 劳伦修·罗迪纳 , BIMSA ) When color meets gravity In this talk I will describe a surprising interplay between representation theory and gravitational consistency, introducing a first-principles framework for deriving sharp and universal constraints on UV completions of gravity. Using the S-matrix bootstrap—where Lorentz invariance, analyticity, unitarity, and causality restrict interactions, I will show that the graviton pole, once seen as an obstruction, becomes a powerful tool. Gravitational consistency enforces the presence of specific irreps of the symmetry group, ruling out spectra that appear viable without gravity. This mechanism provides direct support for the Completeness Hypothesis of the Swampland Program, marking a concrete step toward a rigorous proof of a Swampland conjecture. |
2025-09-03
| 10:00-11:00 Wu-Zhong Guo ( 郭武中 , Hua-Zhong U. Sci. Tech. ) Properties and Generalizations of the Spacetime Density Matrix Recent studies have shown that the concept of entanglement can be extended to causally connected subregions. Starting from correlation functions, one can naturally define a “density matrix” for such regions, which we call the spacetime density matrix. In this talk, I will briefly introduce how to construct the spacetime density matrix and represent it using the Schwinger–Keldysh path integral. We find that by introducing a super-operator, the spacetime density matrix can be expressed more systematically, and on this basis we also derive the corresponding Liouville–von Neumann equation. The super-operator further allows us to introduce two natural generalizations. Finally, I will give examples illustrating entropy-related quantities defined from the spacetime density matrix and its generalizations, as well as their computations in quantum mechanics and quantum field theory. |
| 11:00-12:00 Tomasz Smołka ( University of Warsaw ) Complex transformations in spin interaction analysis The Newman-Janis transformation allows for the simple mapping of the Schwarzschild solution to the Kerr solution. Such procedures can be applied to analyze the interaction of spinning objects. First, I present a simplified model that considers the electromagnetic (Maxwell) interaction of two Kerr-Newman solutions (zero gravity limit). The interaction potential can be computed in specific configurations to all orders in spin. Then I adress a similar issue involving two interacting Kerr solutions in a weak (linearized) field approximation. |
| 14:00-15:00 Yihao Yin ( NUAA, Nanjing ) Low-Spin Solutions to Higher-Spin Gravity Higher-spin gravity in 4D is a set of theories that contain infinitely many interacting higher-spin gauge fields. When we try to construct solutions to such theories, activating the fields of one particular spin very often leads to the activation of (infinitely) many other spins. However, there do exist special solutions that activate only a small number of spins. In my talk I will present two examples of such solutions with only spin-0 and spin-1 activated. I will briefly introduce higher-spin gravity theories before presenting the solutions. |
| 15:00-16:00 Rongxin Miao ( Zhongshan University, Zhuhai ) Gravity Dual of Network and Entanglement We propose the gravity dual of conformal field theory defined in networks (AdS/NCFT), which is the multi-branch generalization of AdS/BCFT and a natural realization of parallel universes. We prove that the multi-junction condition on the Net-brane results in the conservation of energy flux at the network node. We find that the spectrum of gravitational Kaluza-Klein modes on the Net-brane is a mixture of that of AdS/BCFT with Neumann boundary condition and Dirichlet boundary condition, corresponding to the isolated and transparent modes, respectively. We propose that the Ryu-Takayanagi surfaces intersect at the same point on the Net-brane for connected subsystems within the network and verify this with the monotonicity of entanglement entropy. We establish that the network entropy, defined as the difference in entanglement between NCFT and BCFT, is always non-negative and effectively illustrates the network’s complexity. |
2025-09-04
| 10:00-11:00 Bin Chen ( Ningbo University and Peking University ) Structure of Carrollian (conformal) superalgebra In this work, we investigate possible supersymmetric extensions of the Carrollian algebra and the Carrollian conformal algebra in both d=4 and d=3. For the super-Carrollian algebra in d=4, we identify multiple admissible structures, depending on the representations of the supercharges with respect to the Carrollian rotation. Some of these structures can be derived by taking the speed of light c->0 limit from super-Poincar\’e algebra, but others are completely novel. In the conformal case, we derive nontrivial Carrollian superconformal algebras in dimensions d=4 and d=3. Among these, the superconformal algebra in d=4 and one of the algebras in d=3 exhibit isomorphisms to the super-Poincar\’e algebras in d=5 and d=4, respectively. Additionally, we identify a novel, nontrivial superconformal algebra in d=3 that is not isomorphic to any super-Poincar\’e algebra. Remarkably, neither of these constructions requires R-symmetry to ensure the algebraic closure. Given that BMS algebra constitutes the infinite-dimensional extension of the d=3 Carrollian conformal algebra, their supersymmetric extension gives rise to nontrivial superconformal Carrollian algebras. Specifically, we demonstrate the existence of a singlet $super-BMS_4$ algebra emerging from the extension of the d=3 Carrollian superconformal algebra, as well as a multiplet $super-BMS_4$ algebra that does not admit this methodology, as its finite-dimensional subalgebra incorporates supercharges with conformal dimension $\Delta = \pm\frac{3}{2}$. |
| 11:00-12:00 Jie-Qiang Wu ( CAS Key Laboratory of Theoretical Physics ) Quantizing the Proca Field in Global AdS3 Spacetime with the Covariant Phase Space Formalism In this work, we quantize the Proca field in the global AdS3 spacetime with the covariant phase space formalism. Holding the quantization, we compute the correlation function and the thermal partition function, which are the same as the ones from other methods. |
| 14:00-15:00 Azadeh Maleknejad ( Swansea University ) Fermion Creation by Cosmic Perturbations at 1-loop Weyl spin 1/2 fermions, when minimally coupled to Einstein’s gravity, cannot be produced purely gravitationally in an expanding universe at tree level. However, this picture changes at the gravitational 1-loop level in the presence of cosmic perturbations, leading to a new and unavoidable mechanism for gravitational particle production. In this talk, I will explore the theory and phenomenological implications of this new effect. |
| 15:00-16:00 Gabriel Arenas-Henriquez ( YMSC, Tsinghua ) Radiation in fluid/gravity and the flat limit We investigate asymptotically locally anti-de Sitter spacetimes exhibiting radiative behavior, using null gauges that admit well-defined flat limits. The radiative content in the bulk is captured by the super-Poynting vector, which we reinterpret holographically in terms of fluid variables in the dual boundary theory. For algebraically special solutions, we uncover a close connection between bulk radiation and dissipative corrections in the boundary stress tensor, demonstrating a direct link between radiation and entropy production in the boundary fluid. This reveals a rich interplay between radiative dynamics in the bulk and out-of-equilibrium conformal physics at the boundary. We then investigate the flat limit of this correspondence in the context of flat-space holography. In this setting, we obtain the Carrollian analogue of the super-Poynting vector and introduce Celestial observables, such as energy detectors, which emerge naturally from the bulk’s radiative structure. Our analysis shows that bulk radiation sources the Carrollian viscous stress tensor and heat current, which encodes the Bondi news in this framework. We illustrate our results with explicit examples, including Robinson-Trautman spacetimes and accelerating black holes. |
2025-09-05
| 10:00-11:00 René Meyer ( Julius-Maximilians-Universität Würzburg ) Aspects of PT symmetric Non-Hermiticity in AdS/CFT and in SYK models Investigations of non-hermitian quantum systems recently has drawn much interest in the field of holography and the AdS/CFT correspondence. In this talk, I will focus on non-hermiticity of the PT symmetric type and, after a short introduction into the subject, present several results for PT symmetric systems of interest in holography: In the first part of the talk, I will discuss our recent [1] investigation of the phase structure and the interaction induced quantum critical conductivity in a PT symmetric non-hermitian holographic metal. In particular the conductivity shows interesting new features in the different phases, which are qualitatively reproduced in a PT symmetrically deformed version of Landau-Ginzburg theory. In the second part of the talk, I will present analytic and numerical work [2] on the operator size growth in Lindbladian SYK models. I will in particular present a new timescale, the plateau time, after which the operator size growth reaches a plateau. Finally, I will present recent work [3] on the entanglement structure in these Lindbladian SYK models, and a new entanglement measure with better properties for non-hermitian systems. [1] Z.Y. Xian, D. Rodriguez-Fernandez, Z.H. Chen, Y. Liu, R. Meyer, SciPost Physics 16 (2024) [2] J.S. Liu, R. Meyer, Z.Y. Xian, JHEP 08 (2024) [3] Z.H. Chen, R. Meyer, Z.Y. Xian, arXiv:2508.09261 |
| 11:00-12:00 Hossein Babaei Aghbolagh ( Ningbo University ) Root-TT-bar Deformations On Causal Self-Dual Electrodynamics Theories The self-dual condition, which ensures invariance under electromagnetic duality, manifests as a partial differential equation in nonlinear electromagnetism theories. The general solution to this equation is expressed in terms of an auxiliary field, $\tau$, and Courant-Hilbert functions, $\ell(\tau)$, which depend on $\tau$. Recent studies have shown that duality-invariant nonlinear electromagnetic theories fulfill the principle of causality under the conditions $\frac{\partial \ell}{\partial \tau} \ge 1$ and $\frac{\partial^2 \ell}{\partial \tau^2} \ge 0$. In this talk, we investigate theories with two coupling constants that also comply with the principle of causality. We demonstrate that these theories possess a new universal representation of the root-$T\bar{T}$ operator. Additionally, we derive marginal and irrelevant flow equations for the logarithmic causal self-dual electrodynamics. |
Sponsor:
Beijing Institute of Mathematical Sciences and Applications
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