Renyi entropy for spherical monodromy of free scalar fields in even dimensions

TL;DR

This paper investigates the impact of spherical monodromy defects on free scalar fields in even dimensions, computing conformal anomalies, Rnyi, and entanglement entropies, and discusses potential conflicts with previous findings.

Contribution

It introduces a detailed analysis of spherical monodromy effects on conformal scalar fields across even dimensions, including anomaly and entropy calculations, and highlights possible discrepancies with existing literature.

Findings

Conformal anomaly computed in two ways for spherical monodromy defects.

Rnyi and entanglement entropies derived for these defects.

Negative values of the central charge $C_T$ found for certain flux ranges.

Abstract

The effect of a co--dimension--2 spherical monodromy defect on the free--field theory of a conformal scalar is investigated. The conformal anomaly is computed (in two ways) and thence the R\'enyi and entanglement entropies. The $C_T$ central charge is found to be negative for a range of monodromy flux.The calculations are pursued for any even dimensional sphere. A Possible conflict with existing results is raised.