Dynamic generation or removal of a scalar hair

Abstract

In this work, we study the dynamic processes through which the scalar hair of the black holes is generated or detached. To this end, one investigates the temporal evolution of a far-from-equilibrium gravitational system in the framework of a theory featured by non-minimal couplings of a scalar field to the Gauss-Bonnet and Ricci scalar invariants. In our simulations, the initial spacetime is chosen to be either a bald Schwarzschild or a scalarized spherically symmetric black hole. By further introducing an energy injection, which might be perturbative in some cases, the system's evolution is explored. Intriguing features regarding the final fate of the system are observed, sensitively dependent on the initial configurations, perturbations, and the specific metric parameters. In particular, besides the well-known scalarization through which the black hole acquires scalar hair, the dynamic process might also serve to deprive the hair of an initially stable hairy one. Moreover, we elaborate on the temporal evolution of the scalar field, the metrics, and the Misner-Sharp mass of the spacetime. The implications of the present findings are also addressed.

Parity Symmetry Breaking and Kink Hairy Black Hole

“…In the left panels, we show the snapshots of the order parameter at four different time stages, from the initial to the final equilibrium state. At the initial time, the order parameter exhibits a random profile and then evolves and grows rapidly around t ∈ [7,13], later it goes to a profile of some stable kinks in the final equilibrium state. Their corresponding average absolute values |O| are shown in the right panel.…”

“…However, this conjecture was extended and challenged in some exceptional cases, such as the soft hairs near horizon [4], the black holes of non-Abelian Yang-Mills field [5], or in higher dimensional gravity [6], just to list some examples. One can refer to [7] and references therein. Among these, Gubser's argument [8] for the hair of charged scalar fields in a spacetime with a negative cosmological constant was widely applied in the holographic superconducting phenomenon [9].…”

Descalarization by quenching charged hairy black hole in asymptotically AdS spacetime

“…However, these works were limited in the decoupling limit where the nonlinear scalar equation of motion was only evolved on the background from general relativity. Then another mechanism for descalarization by accretion was introduced in [48][49][50][51][52][53]. These works considered the full nonlinear evolution of black holes under large perturbation.…”