Stellar Instability from Parametric Resonance

TL;DR

This paper investigates the stability of charged stellar configurations with complex interior components, revealing conditions under which they become unstable and eject mass, transitioning to a Reissner-Nordström-de Sitter exterior.

Contribution

It introduces a model with interacting vacuum and scalar fields in stellar interiors, analyzing stability and showing how certain parameters lead to instability and mass ejection.

Findings

Interior solutions can be highly unstable under certain parameters.

Instability causes the breakdown of KAM tori and mass ejection.

Stable configurations match Reissner-Nordström-de Sitter spacetime externally.

Abstract

In this paper we examine the stability of stellar configurations in which the interior solution is described by a closed FLRW geometry sourced with a charged pressureless fluid and radiation. An interacting vacuum component and a conformally coupled massive scalar field are also included. Given a simple factor for the energy transfer between the pressureless fluid and the vacuum component we obtain bounded interior oscillatory solutions. We show that in proper domains of the parameter space the interior dynamics is highly unstable so that the break of the KAM tori leads to a disruptive ejection of mass. For such configurations the interior solution asymptotically matches an exterior Reissner-Nordstr\"om-de Sitter spacetime.