Island Hopping 2020: from Wormholes to Averages

Contribution List

1. Causal symmetry breaking: the EFT description of quantum chaos

Julian Sonner

16/11/2020, 16:00

Abstract:

Quantum chaotic systems are often defined via the assertion that their spectral statistics coincides with, or is well approximated by, random matrix theory. In this talk I will explain how the universal content of random matrix theory emerges as the consequence of a simple symmetry-breaking principle and its associated Goldstone modes. This approach gives a natural way to identify...

2. The time to the black hole singularity from thermal one point functions

Juan Maldacena

16/11/2020, 17:00

3. Informal interactions/Virtual hanging

16/11/2020, 18:00

4. Global symmetry, Euclidean gravity, and the black hole information problem

Daniel Harlow

16/11/2020, 20:00

5. Discussion Session: To average or not to average

Douglas Stanford, Raphael Bousso, Steve Giddings

16/11/2020, 21:00

6. Collision in the interior of wormhole

Ying Zhao

17/11/2020, 16:00

Abstract:

The Schwarzschild wormhole has been interpreted as an entangled state. If Alice and Bob fall into each of the black hole, they can meet in the interior. We interpret this meeting in terms of the quantum circuit that prepares the entangled state. Alice and Bob create growing perturbations in the circuit, and we argue that the overlap of these perturbations represents their...

7. Islands beyond AdS

Edgar Shaghoulian

17/11/2020, 17:00

Abstract:

I will discuss the appearance of islands and replica wormholes in flat and cosmological spacetimes. I will also discuss general consistency conditions that guide the search for such nontrivial saddles in the gravitational path integral.

8. Informal interactions/Virtual hanging

17/11/2020, 18:00

9. Observations of Hawking radiation: the Page curve and baby universes

Henry Maxfield

17/11/2020, 20:00

Abstract:

It has long been argued that black holes can be modeled as unitary quantum systems with density of states given by the Bekenstein-Hawking formula. It now seems that this idea is realised within semiclassical gravity, without using details of the UV completion or assuming duality. I will describe this in an asymptotically flat setting using Lorentz-signature gravitational path...

10. Perturbative and Non-Perturbative Insights into Deformed JT Gravity using Random Matrix Ensembles.

Clifford Johnson

17/11/2020, 21:00

11. A general approximation scheme for addressing the black hole information paradox

Hong Liu

18/11/2020, 16:00

Abstract:

We develop a general approximation scheme for calculating quantum informational properties of a pure state that has equilibrated in a non-integrable quantum many-body system. For gravity systems, such as those involving black holes, this approximation gives a prescription for calculating entanglement entropies using Euclidean path integrals which is manifestly consistent with...

12. To average or not to average

Jan de Boer

18/11/2020, 17:00

Abstract:
In this talk I will describe a possible interpretation of genus two wormholes in AdS3 in terms of a
suitable averaging procedure in the dual field theory, and connect this to random properties of
OPE coefficients. I will discuss possible lessons from this for the question whether or not gravity
is intrinsically an averaged theory. Mostly based on arXiv:2006.05499 with Alex Belin.

13. Informal interactions/Virtual hanging

18/11/2020, 18:00

14. Gravity without Ensembles

Jamie Sully

18/11/2020, 20:00

15. Discussion: Firewalls

Ahmed Almheiri, Daniel Jafferis, Herman Verlinde

18/11/2020, 21:00

16. Holographic duality for averaged free CFTs

Tom Hartman

19/11/2020, 16:00

Abstract:
I will describe how the modular bootstrap leads us toward a holographic duality for 2d Narain CFTs averaged over moduli. The bulk theory is a 3d Chern-Simons-like theory of "U(1) gravity." Although this theory has no Einstein term, it has composite gravitons and other features similar to ordinary 3d gravity, so it may be a good place to test ideas about ensemble averaging in...

17. More on Holographic duality for averaged free CFTs

Alex Maloney

19/11/2020, 17:00

Abstract:
I will continue to explore the idea that certain theories of gravity in Anti-de Sitter space are dual to an average over an ensemble of quantum theories, rather than to a specific quantum theory. The average over Narain’s family of two-dimensional conformal field theories which describe free bosons is given by the Siegel-Weil formula, which can be computed at any genus and for...

18. Informal interactions/Virtual hanging

19/11/2020, 18:00

19. Some comments on wormholes and factorization

Phil Saad

19/11/2020, 20:00

Abstract:
Spacetime wormholes have played an important role in recent progress in black hole physics. However, in the context of AdS/CFT, these wormholes lead to a basic puzzle: the "factorization problem", introduced by Maldacena and Maoz. In this talk we will explore this issue in some simple models, including Marolf and Maxfield's topological model, JT gravity, and the SYK model. These...

20. Wormholes, random matrices, and (non-)factorization in d>2

Kristan Jensen

19/11/2020, 21:00

Abstract:

In the first half of this talk, I will discuss wormholes in pure 3d Euclidean gravity with negative cosmological constant. We compute a wormhole amplitude, the path integral over Euclidean spaces which smoothly connect two hyperbolic regions with torus boundary and topology torus times line. This is a 3d version of the “double trumpet” of JT gravity. From this amplitude we...

21. Gravitational Perturbations of Extreme Kerr Revisited

Alejandra Castro

20/11/2020, 16:00

22. Discussion: The Final State

Andrea Puhm, Juan Maldacena, Suvrat Raju

20/11/2020, 17:00

23. Informal interactions/Virtual hanging

20/11/2020, 18:00

24. Life without pythons would be so simple

Geoff Penington

20/11/2020, 20:00

25. Confinement, Wormholes, and Cosmology

Mark Van Raamsdonk

20/11/2020, 21:00