EZ gauge is singular at the event horizon

TL;DR

The paper proves that the EZ gauge used in black-hole perturbation theory becomes singular at the event horizon, impacting the analysis of gravitational self-force effects.

Contribution

It demonstrates the inherent singularity of the EZ gauge at the event horizon, clarifying limitations in black-hole perturbation methods.

Findings

EZ gauge is singular at the event horizon

Implications for gravitational self-force analysis

Limits of EZ gauge applicability

Abstract

We prove that the EZ gauge of black-hole perturbation theory, introduced by the late Steve Detweiler in his exploration of the physical consequences of the gravitational self-force, is necessarily singular at the event horizon.