activity
20232026
most citedNormal Modes of the Stretched Horizon: A Bulk Mechanism for Black Hole Microstate Level Spacing

1 citations · 1 across the 15 of their papers we have counts for

collaborators

16 papers

hep-th2026

Quantum Gravity from Gluing Consistency: AdS/CFT to Spin-Foams

Chethan Krishnan

We argue that BF theory with gauge group provides a SymTFT ''skeleton'' for building AdS/CFT pairs via gluing consistency as the bootstrap principle, loosel…

hep-th2026

Building a Quantum Black Hole Microstate: A Bulk Path Integral for a Heavy Virasoro Primary

Chethan Krishnan, Rajdeep Mitra

Consider level- Chern-Simons theory on a semi-infinite solid cylinder, with a Wilson line in the unitary principal continuous series inserted along the…

hep-th2026

Wilson Towers as Local Bulk Fields

Vishal Gayari, Chethan Krishnan

Multi-winding Wilson loops (``Wilson spools'') in 2+1-dimensional gravity can reproduce one-loop partition functions of local free fields in the bulk. Bulk free fields have a secon…

hep-th2026

Geodesics from Quantum Field Theory: A Case Study in AdS

Vaibhav Burman, Chethan Krishnan, Livesh Parajuli

Localized one-particle states of a quantum field theory--whether in flat space or on a curved background--are expected to exhibit geodesic motion in an appropriate semiclassical re…

hep-th2026

Holography, Brick Wall and a Little Hierarchy Problem

Vishal Gayari, Chethan Krishnan, Pradipta S. Pathak

We propose a heuristic for the brick wall in AdS/CFT: the location where a boundary mode's local bulk energy reaches a (Planckian) UV cut-off. This accomplishes two things: (a) the…

hep-th2026

Holography with an Inner Boundary: A Smooth Horizon as a Sum over Horizonless States

Chethan Krishnan, Pradipta S. Pathak

The (holomorphic) partition function of the Euclidean BTZ black hole with boundary modulus , is the -image of the Virasoro vacuum character, . This object…

hep-th2025

Virasoro Blocks and Trouble at the Euclidean Horizon

Aaditya Datar, Chethan Krishnan

In the semi-classical () limit, 4-point HLLH correlators in 2D CFTs exhibit periodic Euclidean singularities. Periodic singularities in Euclidean time are a g…

hep-th2025

An Analytic Zeta Function Ramp at the Black Hole Thouless Time

Pallab Basu, Suman Das, Chethan Krishnan

Black hole normal modes have intriguing connections to logarithmic spectra, and the spectral form factor (SFF) of is the mod square of the Riemann zeta function (RZF…

hep-th2024

A Central Charge for sub-AdS Holography

Abir Ghosh, Chethan Krishnan, Adinath Mahalingam

We synthesize and sharpen various observations about sub-AdS holography in the literature to associate a central charge to sub-AdS scales of AdS x geometries. A key ingredient…

hep-th2024

Holomorphic Factorization at the Quantum Horizon

Chethan Krishnan, Pradipta S. Pathak

We identify a horizon-skimming limit under which wave equations around large classes of black holes allow a determination of their low-lying (quasi-)degenerate normal modes. Buildi…

hep-th2024

A Bottom-Up Approach to Black Hole Microstates

Vaibhav Burman, Chethan Krishnan

In arXiv:2312.14108, we argued that a sliver at the black hole mass in the Hilbert space of a quantum field theory on an AdS black hole with a stretched horizon, has many desirable…

hep-th2024

Young Black Holes Have Smooth Horizons: A Swampland Argument

Chethan Krishnan, Ranjini Mondol

It has been suggested that black hole microstates in string theory may have "no interiors". The arguments of arXiv:2312.14108 suggest that even if this were the case, conventional…

hep-th2023★ 1 cited

Normal Modes of the Stretched Horizon: A Bulk Mechanism for Black Hole Microstate Level Spacing

Chethan Krishnan, Pradipta S. Pathak

In 1984, 't Hooft famously used a brickwall (aka stretched horizon) to compute black hole entropy up to a numerical pre-factor. This calculation is sometimes interpreted as due to…

hep-th2023

A Smooth Horizon without a Smooth Horizon

Vaibhav Burman, Suchetan Das, Chethan Krishnan

Recent observations on type III algebras in AdS/CFT raise the possibility that smoothness of the black hole horizon is an emergent feature of the large- limit. In this paper, we…

hep-th2023

A Holographic Entanglement Entropy at Spi

Abir Ghosh, Chethan Krishnan

Defining finite entanglement entropy for a subregion in quantum field theory requires the introduction of two logically independent scales: an IR scale that controls the size of th…

hep-th2023

State-independent Black Hole Interiors from the Crossed Product

Chethan Krishnan, Vyshnav Mohan

Opinion is divided about the nature of state dependence in the black hole interior. Some argue that it is a necessary feature, while others argue it is a bug. In this paper, we con…