3 papers
gr-qc2025
Sufficient conditions for unbounded superradiance in black hole spacetimes sourced by nonlinear electrodynamics
Marco A. A. de Paula, Luiz C. S. Leite, LuÃs C. B. Crispino
Recently, it has been reported that black holes (BHs) sourced by nonlinear electrodynamics (NED) can trigger unbounded superradiance, i. e., the total absorption cross section -- t…
gr-qc2025
Good tachyons, bad bradyons: role reversal in Einstein-nonlinear-electrodynamics models
Marco A. A. de Paula, Haroldo C. D. Lima Junior, Pedro V. P. Cunha +2
In relativistic mechanics, the 4-velocity and the 4-momentum need not be parallel. This allows their norm to have a different sign. This possibility occurs in nonlinear electrodyna…
gr-qc2024
Superradiant instability of a charged regular black hole
Sam R. Dolan, Marco A. A. de Paula, Luiz C. S. Leite +1
We show that a charged, massive scalar field in the vicinity of an electrically-charged Ayón-Beato-GarcÃa (ABG) regular black hole has a spectrum of quasibound states that (in a…