Statistical mechanics, Algebra, and Geometry

Contribution List

1. Symmetric Orbfiolds, thermal universality and stringy von Neumann algebras

Alexandre Belin (Universita & INFN, Milano-Bicocca (IT))

03/02/2025, 10:15

Symmetric orbifolds are 2d CFTs with universal properties in the large N limit, mimicking many desired properties of holographic CFTs. In particular, the thermal partition function is universal and agrees with that of 3D gravity. I will present some new results for the universality of symmetric orbiflds: the thermal correlation functions at large N agree with those on the BTZ background. Along...

2. TBA

Jan de Boer (Nikhef National institute for subatomic physics (NL))

03/02/2025, 16:00

3. A microscopic model of de Sitter spacetime with an observer

Herman Verlinde (Princeton University)

03/02/2025, 17:15

I describe a simple microscopic quantum mechanical model of low-dimensional de Sitter holography with an observer. Using semiclassical gravity and elementary thermodynamic considerations, I’ll derive a formula for the total entropy of a 3D de Sitter universe with an observer. I then show that this entropy formula exactly matches the known spectral density of the double scaled SYK model.

4. discussion

participants

03/02/2025, 20:30

5. Gravitational Boundary Modes in Finite Volume

Ruben Monten (CERN)

04/02/2025, 09:00

n order to understand the structure of the Hilbert space of gravitational theories, we study one of its universal sectors: the “large gauge” modes, which live on (asymptotic) boundaries. For low-dimensional AdS gravity, we can move them away from the conformal boundary and find that the resulting theory is related to the $T \bar{T}$ deformation. I will discuss how this “beyond-Wilsonian”...

6. Chaos, Eigenstate Thermalization, and 3D Gravity

Diego Liska (Universite de Geneve (CH))

04/02/2025, 10:15

In recent years, it has become clear that the path integral of semiclassical 3D gravity offers a "coarse-grained" description of its holographic 2D CFT. This relationship is particularly transparent when considering the statistical moments of operator product expansion (OPE) coefficients in the CFT. In this talk, I will explore the statistical properties of OPE coefficients through the...

7. Krylov complexity and the bulk Hilbert space of DSSYK

Ruth Shir

04/02/2025, 16:00

Within the framework of the AdS/CFT correspondence, the time dynamics of black holes in the bulk hints to the existence of boundary observables that evolve for very long time-scales. It was conjectured that quantum complexity has the correct features to be a candidate boundary observable. However, none of the proposed notions of quantum complexity yielded a precise bulk-boundary correspondence...

8. poster session

participants

04/02/2025, 17:15

9. discussion

participants

04/02/2025, 20:30

10. Bra-Ket Wormholes

Joshua Kames King

05/02/2025, 09:00

Based on 2408.08351 and some work in progress. We study a model for the initial state of the universe based on a gravitational path integral that includes connected geometries which simultaneously produce bra and ket of the wave function. We argue that a natural object to describe this state is the Wigner distribution, which is a function on a classical phase space obtained by a certain...

11. Spinning up the black hole – string correspondence

Andrea Puhm

05/02/2025, 10:15

The correspondence principle between strings and black holes is a general framework for matching black holes and massive states of fundamental strings at a point where their physical properties (such as mass, entropy and temperature) smoothly agree with each other. As such it offers a statistical interpretation of black hole entropy. I will discuss the extension of this correspondence...

12. discussion

05/02/2025, 20:30

13. Stringy Causal Structure from Algebras”

Nima Lashkari

06/02/2025, 09:00

We will discuss the emergence of Stringy spacetime from the chaos in modular flow of future algebras.
We will discuss the modular ergodic hierarchy, and prove a sufficient condition for the emergence of Stringy AdS_2 from modular intersections.

14. An intrinsic cosmological observer

Antony Speranza (University of Illinois, Urbana-Champaign)

06/02/2025, 10:15

There has been much recent interest in the necessity to include an observer degree of freedom in the description of local algebras in semiclassical gravity. In this talk, I will describe an example where the observer can be constructed intrinsically from the quantum fields. This construction involves the slow-roll inflation example recently analyzed by Chen and Penington, in which the...

15. TBA

Daniel Jafferis

06/02/2025, 16:00

16. Strings from Feynman Diagrams

Edward Mazenc (ETH Zürich)

06/02/2025, 17:15

Over 50 years ago, 't Hooft observed the similarity between the Feynman diagram expansion of a large N gauge theory and the topological expansion of a string theory. The purpose of this talk is to make this idea precise for a protected subsector of the AdS/CFT correspondence. Concretely, we show how the Feynman diagram expansion of correlation functions in N=4 SYM preserving half the...

17. discussion

participants

06/02/2025, 20:30

18. Thermal Bootstrap of Matrix Quantum Mechanics

Barak Gabai (EPFL - Ecole Polytechnique Federale Lausanne (CH))

07/02/2025, 09:00

I will explain the implementation of a bootstrap method that combines Schwinger-Dyson equations, thermal inequalities, and semidefinite relaxations of matrix logarithm in the ungauged one-matrix quantum mechanics, at finite rank N as well as in the large N limit, to determine finite temperature observables. I will show plots of these observables (determined using the bootstrap) that...

19. Operator product expansion, geodesics and black hole singularities

Andrei Parnachev

07/02/2025, 10:15

We observe features of black hole singularities in finite temperature holographic correlators of generic scalar operators.
We also elucidate the relation between geodesics in the AdS-Schwarzschild background and the Operator Product Expansion in the boundary CFT.