Corrected Hawking Temperature and Final State of Black Hole Evaporation Under GEVAG Framework

TL;DR

This paper introduces a modified Hawking temperature within the GEVAG framework, accounting for a varying gravitational constant, and shows it resolves previous issues with black hole remnants and entropy corrections.

Contribution

It derives a corrected Hawking temperature incorporating GEVAG effects, aligning with GUP results and addressing remnant temperature issues, plus formulas for energy and Bekenstein bound under entropy corrections.

Findings

Hawking temperature includes a second term related to G_eff variation.

The first temperature term matches GUP-based results.

The second term drives temperature to zero at minimum black hole mass.

Abstract

In the GEVAG (Generalized Entropy Varying-G) framework, any generalization to horizon entropy leads to a varying gravitational "constant" $G_\text{eff}$ that is a function the horizon area. In this work, it is shown that if we promote $G_\text{eff}$ to be valid in the neighborhood of the horizon, then Hawking temperature consists of two terms, the second of which is related to the variation of $G_\text{eff}$. When applied to the logarithmic correction of the entropy, as is common across various quantum gravity approaches, the first term in the Schwarzschild black hole temperature exactly agrees with that obtained from utilizing generalized uncertainty principle (GUP), while the second term improves on the GUP result by driving the Hawking temperature to zero as the black hole approaches a minimum mass. This resolves the inconsistency in the GUP result concerning a nonzero temperature minimum mass remnant. This work also derives simple general formulas for both the thermodynamic energy and the Bekenstein bound for any correction to the area law under the same assumption that $G_\text{eff}$ can be extended off-shell in the horizon neighborhood. The (generalized) Bekenstein bound can be interpreted as a statement regarding the renormalization group scaling dimension of the entropy functional $f(A)$ and the naturalness of the theory.