Holographic entanglement entropy in Chern-Simons gravity with torsion

TL;DR

The paper addresses how to incorporate torsion into holographic entanglement entropy for a boundary theory dual to five-dimensional Chern–Simons gravity with axial torsion. It presents two complementary prescriptions: (i) promote the boundary induced Ricci scalar to its RC counterpart in the entanglement entropy, and (ii) generalize the entropy functional to RC curvature and evaluate on torsionful backgrounds. Both approaches yield a universal torsion-induced logarithmic divergence in the 4D CFT entanglement entropy, with the coefficient governed by the torsion strength. The authors validate this via Fefferman–Graham analysis and explicit cylinder geometry calculations, finding consistent log terms, which supports the proposed RC holography framework and its relation to RC Wald entropy concepts.

Abstract

Holographic entanglement entropy is a key concept linking quantum information theory and gravity. Since the original conjecture of Ryu and Takayanagi, holographic entanglement entropy has been generalized beyond Einstein--Hilbert gravity to include higher-curvature corrections. In most existing generalizations, however, it is implicitly assumed that the bulk spacetime geometry is Riemannian, i.e. torsion-free. Here we propose a prescription for incorporating torsion into holographic entanglement entropy in the boundary theory dual to five-dimensional Chern--Simons gravity. We argue that the entanglement entropy acquires an additional universal divergent term proportional to the logarithm of the UV cutoff, and that this term is generated solely by torsion.