Weak cosmic censorship with self-interacting scalar and bound on charge to mass ratio

TL;DR

This paper investigates how self-interacting charged scalar fields influence cosmic censorship in Einstein-Maxwell theory, establishing bounds on charge-to-mass ratios that depend on scalar self-interaction parameters, thereby potentially removing counterexamples to cosmic censorship.

Contribution

It introduces bounds on charge-to-mass ratios for self-interacting scalar fields that differ from the free scalar case, showing how these interactions can uphold cosmic censorship.

Findings

Counterexamples to cosmic censorship exist without scalar fields.

Large charge scalar fields can remove these counterexamples.

Bounds on charge-to-mass ratio depend on scalar self-interaction parameters.

Abstract

We study the model of Einstein-Maxwell theory minimally coupling to a massive charged self-interacting scalar field, parameterized by the quartic and hexic coupling, labelled by $\lambda$ and $\beta$, respectively. In the absence of scalar field, there is a class of counterexamples to cosmic censorship. Moveover, we investigate the properties of full nonlinear solution with nonzero scalar field, and argue that, by assuming massive charged self-interacting scalar field with sufficiently large charge above one certain bound, these counterexamples can be removed. In particular, this bound on charge for self-interacting scalar field is no longer equal to the weak gravity bound for free scalar case. In the quartic case, the bounds are below free scalar case for $\lambda<0$, while above free scalar case for $\lambda>0$. Meanwhile, in the hexic case, the bounds are above free scalar case for both $\beta>0$ and $\beta<0$.