Black Hole Information in Holography and String Theory

Contribution List

1. Welcome Address

08/02/2025, 09:15

Speaker: Sudhir K. Vempati
Chair CHEP

2. Quantising JT Gravity and It's Extensions (Sandip Trivedi)

08/02/2025, 09:30

Speaker: Sandip Trivedi
Abstract: We will discuss the canonical quantisation of Jackiw - Teitleboim Gravity, and similar models, in 2 dimensions.

3. Black Holes and Higher Derivative Gravity (Nilay Kundu)

08/02/2025, 10:15

Speaker: Nilay Kundu

4. Coffee Break

08/02/2025, 11:00

5. Index for Black Holes in N=2 Supergravity (Amitabh Virmani)

08/02/2025, 11:30

Speaker : Amitabh Virmani

Abstract:
We compute the supersymmetric index of half BPS black holes in N=2 supergravity with higher curvature corrections and show that the result agrees with the degeneracy of supersymmetric extremal black holes carrying the same charges.

6. The Black hole IR triangle (Nava Gaddam)

08/02/2025, 12:15

Speaker: Nava Gaddam

Abstract:
I will argue that there is an emergent infrared triangle near the horizon of a black hole, analogous to the one in flat space. In scalar QED in a Schwarzschild background, I will show that the Ward identities corresponding to near-horizon asymptotic symmetries match exactly with a new emergent leading soft photon theorem that can be derived in an effective...

7. Lunch Break

08/02/2025, 13:00

8. Wigner negativity, Random matrices and Gravity (Onkar Parikar)

08/02/2025, 14:30

Speaker: Onkar Parikar
Abstract:
For any state in a D-dimensional Hilbert space with a choice of an ordered basis, one can define a discrete version of the Wigner function — a quasi-probability distribution which represents the state on a discrete phase space. The Wigner function can, in general, take on negative values, and the amount of negativity in the Wigner function of a state can be...

9. TBA(Debjyoti Sarkar)

08/02/2025, 15:15

Speaker : Debjyoti Sarkar

10. Coffee Break

08/02/2025, 16:00

11. Black(ish) Holes (Arnab Kundu)

08/02/2025, 16:30

Speaker: Arnab Kundu
Abstract: In this talk, we will review some recent progress on
understanding how an ad hoc Dirichlet boundary that is placed in front of
an event-horizon can capture certain quantum chaotic features of the black
hole one-loop determinant sector. We will further discuss how quasi-normal
modes are encoded within the corresponding normal modes. We will also
comment...

12. Topics in von Neumann algebras and semiclassical gravity (Suneeta Varadarajan)

09/02/2025, 09:30

Speaker : Suneeta Varadarajan
Abstract: The generalized second law (GSL) in semiclassical gravity was proposed in order that the second law of thermodynamics be valid near black holes. We first discuss a proof of the GSL using crossed product constructions in von Neumann algebras. Next we discuss a recent idea by Gesteau and Liu to describe stringy horizons holographically in a purely von...

13. TBA (Gautam Mandal)

09/02/2025, 10:15

Speaker: Gautam mandal

14. Coffee Break

09/02/2025, 11:00

15. Supersymmetric deformations of $AdS_3 \times S^3$ and hair modes (Yogesh Srivastava)

09/02/2025, 11:30

Speaker: Yogesh Srivastava
Abstract: The 4D-5D connection allows us to view the near-horizon geometry as part of a 4D Black Hole or a 5D Black Hole. The discrepancy between the entropy/index in the two cases is resolved by introducing hair modes which live outside the horizon. After a review, we discuss the construction and analysis of modes in Poincare AdS_3 ×S^3 which connect to hair modes...

16. Statistical chaos in excited string scattering (Diptarka Das)

09/02/2025, 12:15

Speaker: Diptarka Das
Abstract : We review recent amplitude results in tree level bosonic string theory that involve highly excited string states. We show how random matrix correlations are present in these scattering amplitudes. We conclude by highlighting certain semiclassical and asymptotic features of these amplitudes which lend support to the Horowitz-Polchinski-Susskind black hole...

17. Lunch Break

09/02/2025, 13:00

18. Quantum fields on maximal slices (Anurag Kaushal )

09/02/2025, 14:30

Speaker: Anurag Kaushal
Abstract: We study the semi-classical dynamics of a scalar field in the background of a black hole in an asymptotically AdS (AAdS) spacetime, in the framework of the Hamiltonian formulation of General Relativity. The small diffeomorphism (gauge) symmetries generated by the Hamiltonian and momentum constraints are completely fixed by the maximal slicing and spatial...

19. Holographic observers for time band algebras (Suvrat Raju)

09/02/2025, 15:15

Speaker: Suvrat Raju
Abstract: We study the algebra of observables in a time band on the boundary of anti-de Sitter space in a theory of quantum gravity. Strictly speaking this algebra does not have a commutant because products of operators within the time band gives rise to operators outside the time band. We show that in a state where the bulk contains a macroscopic observer, it is possible...

20. Coffee Break

09/02/2025, 16:00

22. Thank you Ceremony

09/02/2025, 16:30

21. Black Holes and Higher Derivative Gravity (Nilay Kundu)

Speaker: Nilay Kundu