Finiteness of entanglement entropy in a quantum black hole

A logarithmic but divergent term usually appears in the computation of entanglement entropy circumferencing a black hole, while the leading quantum correction to the Bekenstein-Hawking entropy also takes the logarithmic form. A quench model of CFT within finite Euclidean time was proposed by Kuwakino and Wen (JHEP, 05 (2015) 099) to regard this logarithmic term as entanglement between radiation and the black hole, and this proposal was justified by the alternative sign for n-partite quantum information. However, this preliminary form suffers from the notorious divergence at its low-temperature limit. In this letter, we propose a modified form for black-hole entanglement entropy such that the divergence sickness can be cured. We discuss the final stage of a black hole due to this modification and its relation to the Renyi entropy, higher-loop quantum correction and higher-spin black holes. Copyright (C) EPLA, 2016