Regularity of the stress-energy tensor for extremal Reissner-Nordstrom black holes

TL;DR

This paper calculates the stress-energy tensor for specific quantum fields around extremal Reissner-Nordstrom black holes, demonstrating its regularity at the horizon, which challenges earlier claims of singular behavior.

Contribution

It provides the first explicit calculation showing the regularity of the stress-energy tensor at the horizon for these black holes, countering previous assertions of divergence.

Findings

Stress-energy tensor is regular at the horizon.

Contradicts earlier claims of divergence.

Supports the physical viability of extremal black holes.

Abstract

We calculate the expectation values of the stress-energy tensor for both a massless minimally-coupled and dilaton-coupled 2D field propagating on an extremal Reissner-Nordstrom black hole, showing its regularity on the horizon in contrast with previous claims in the literature.