Nonlinear dynamics of hot, cold and bald Einstein-Maxwell-scalar black holes in AdS spacetime

TL;DR

This paper studies the nonlinear dynamics and stability of Einstein-Maxwell-scalar black holes in AdS spacetime, revealing critical phenomena, dynamical barriers, and unique transition behaviors between different states.

Contribution

It introduces a detailed analysis of dynamical transitions, instability mechanisms, and critical phenomena in Einstein-Maxwell-scalar black holes, highlighting the role of scalar field accretion and coupling effects.

Findings

Unstable excited states have a single unstable mode linked to tachyonic instability.

Critical phenomena depend on scalar-Maxwell coupling strength.

Existence of special parameters where perturbations do not trigger instability.

Abstract

We investigate the dynamical transition processes of an Einstein-Maxwell-scalar gravitational system between two local ground states and an excited state in the anti-de Sitter spacetime. From the linear perturbation theory, only the excited state possesses a single unstable mode, indicating the dynamical instability. Such an instability is associated with the tachyonic instability due to the presence of an effective potential well near the event horizon. From the nonlinear dynamics simulation, through the scalar field accretion mechanism, the critical phenomena in the transition process of the gravitational system between the two local ground states are revealed. The threshold of the accretion strength indicates the existence of a dynamical barrier in this transition process, which depends on the coupling strength between the scalar and Maxwell fields. On the other hand, for the unstable excited state, there exists a special kind of critical dynamics with a zero threshold for the perturbation strength. The perturbations of different signs push the gravitational system to fall into different local ground states. Interestingly, in an extended parameter space, there exist specific parameters such that the perturbations of non-zero amplitude fail to trigger the single unstable mode of the excited state.