English

Root-$T\overline{T}$ deformed CFT partition functions at large central charge

High Energy Physics - Theory 2025-12-03 v3 General Relativity and Quantum Cosmology

Abstract

In this work, we investigate the partition function of 2d CFT under root-TTˉT\bar{T} deformation. We demonstrate that the deformed partition function satisfies a flow equation. At large central charge sector, the deformed partition function reduces to a redefinition of the modular parameters, which preserves modular invariance under the deformed parameters. We then derive a Cardy-like formula for the asymptotic density of states using modular bootstrap trick. In the context of AdS/CFT, it was proposed the root-TTˉT\bar{T} deformed CFT corresponds to the AdS3_3 with certain deformed boundary condition. We show the deformed BTZ black hole is a quotient of hyperbolic space. In terms of Chern-Simons formulation, we compute the root-TTˉT\bar{T} deformed BTZ black hole entropy and find that it obeys a Cardy-like formula, which is consistent with the modular bootstrap result. Furthermore, employing the Wilson spool technique, we compute the one-loop partition functions for the root-TTˉT\bar{T} deformed AdS3_3 geometry. Our results reveal an exact match between one-loop gravitational partition function and the large cc expansion of root-TTˉT\bar{T} deformed CFT partition function.

Keywords

Cite

@article{arxiv.2505.12093,
  title  = {Root-$T\overline{T}$ deformed CFT partition functions at large central charge},
  author = {Miao He},
  journal= {arXiv preprint arXiv:2505.12093},
  year   = {2025}
}

Comments

37 pages, v2: references added,v3: minor revision, published version

R2 v1 2026-07-01T02:18:49.215Z