Evaporating black holes and late-stage loss of soft hair

TL;DR

The paper discusses a paradox in black hole evaporation where the loss of soft hair at late stages reintroduces the firewall problem, challenging existing resolutions of the information paradox.

Contribution

It identifies a new 'hair-loss paradox' highlighting the limitations of current models in maintaining soft hair during black hole evaporation.

Findings

Decoupling of early and late radiation fails at late evaporation stages.

Soft hair loss occurs as black holes evaporate, undermining information retention.

The paradox suggests new challenges for resolving the black hole information problem.

Abstract

We present a paradox for evaporating black holes, which is common in most schemes trying to avoid the firewall by decoupling early and late radiation. At the late stage of the black hole evaporation, the decoupling between early and late radiation can not be realized because the black hole has a very small coarse-grained entropy, then we are faced with the firewall again. We call the problem hair-loss paradox as a pun on losing black hole soft hair during the black hole evaporation and the situation that the information paradox has put so much pressure on researchers.