Quasinormal modes for massive charged scalar fields in Reissner-Nordstrom dS black holes: anomalous decay rate

The anomalous decay rate of the quasinormal modes occurs when the longest-lived modes are the ones with higher angular number. Such behaviour has been recently studied in different static spacetimes, for uncharged scalar and fermionic perturbations, being observed in both cases. In this work we consider the propagation of charged massive scalar fields in the background of Reissner-Nordstrom-de Sitter black holes and we mainly study the effect of the scalar field charge in the spectrum of quasinormal frequencies, as well as, its effect on the anomalous decay rate. Mainly, we show that the anomalous behaviour is present for massive charged scalar fields as well, and a critical value of scalar field mass exists, beyond which the behaviour is inverted. However, there is also a critical value of the parameter qQ of the charge of the scalar field and of the charge of the black hole, which increases when the cosmological constant increases, and beyond the critical value the anomalous behaviour of the decay rate could be avoided for the fundamental mode.

Automated summary

This study considers the propagation of charged massive scalar fields in the background of Reissner-Nordstrom-de Sitter black holes and investigates the effect of the scalar field charge on the spectrum of quasinormal frequencies and the anomalous decay rate. The results show that the anomalous behavior also exists for charged massive scalar fields, and there is a critical value that leads to a reversal of this behavior. Additionally, there is a critical value of the charge parameter and the black hole charge, which increases with the cosmological constant, and beyond this critical value, the anomalous behavior of the decay rate can be avoided for the fundamental mode.