Implications of the Weak Gravity Conjecture for Tidal Love Numbers of Black Holes

TL;DR

This paper explores how the Weak Gravity Conjecture constrains the tidal Love numbers of black holes by analyzing higher-order curvature corrections, revealing that such corrections induce non-zero tidal deformability.

Contribution

It demonstrates the impact of cubic order Riemann curvature corrections on black hole tidal Love numbers within the framework of the Weak Gravity Conjecture.

Findings

Higher-order derivative corrections induce non-zero tidal Love numbers.

Pure General Relativity predicts zero tidal Love numbers for black holes.

The interplay constrains effective field theories of gravity.

Abstract

The Weak Gravity Conjecture indicates that extremal black holes in the low energy effective field theory should be able to decay. This criterion gives rise to non-trivial constraints on the coefficients of higher-order derivative corrections to gravity. In this paper, we investigate the tidal deformability of neutral black holes due to higher-order derivative corrections. As a proof of concept, we consider a correction of cubic order in the Riemann curvature tensor. The tidal Love numbers of neutral black holes receive leading-order corrections from higher-order derivative terms, since black holes in pure General Relativity have vanishing tidal Love number. We conclude that the interplay between the tidal deformability of black holes and the Weak Gravity Conjecture provides useful information about the effective field theory.