Non-Local Effects in String Black Holes

TL;DR

This paper investigates how non-local effects from string theory modify black hole properties, showing they preserve topology but violate thermodynamic laws, and exploring a non-perturbative, finite quantum gravity regime.

Contribution

It demonstrates that non-local string effects do not change black hole topology but lead to thermodynamic law violations and proposes a non-perturbative, ultraviolet-finite quantum gravity model.

Findings

Non-local effects do not alter black hole topology.

Violations of the area law and Hawking's first law occur due to string effects.

Hawking temperature approaches zero in the non-perturbative limit.

Abstract

We consider modifications to general relativity due to non-local string effects by using perturbation theory about the 4-dimensional Schwarzschild black hole metric. In keeping with our interpretation in previous works of black holes as quantum p-branes we investigate non-local effects due to a critical bosonic string compactified down to 4 dimensions. We show that non-local effects do not alter the spacetime topology (at least perturbatively), but they do lead to violations of the area law of black hole thermodynamics and to Hawking's first law of black hole thermodynamics. We also consider a simple analytic continuation of our perturbaive result into the non-perturbative region, which yields an ultraviolet-finite theory of quantum gravity. The Hawking temperature goes to zero in the non-perturbative region (zero string tension parameter), which is consistent with the view that Planck-size physics is quantum mechanical.