Echoes of charged black-bounce spacetimes

Abstract

In present work, the evolution of scalar field and electromagnetic field under the background of the charged black-bounce spacetimes are investigated, and we obtain an obvious echoes signal which appropriately reports the properties of the charged black-bounce spacetimes and disclose the physical reasons behind such phenomena. Furthermore, by studying the quasinormal ringdown, we analyze the three states of the charged black-bounce spacetimes in detail, our results show that the echoes signal only appears when (|Q| ≤ m) and (|l| > m + m 2 − Q 2 ) in this spacetime, while when the parameters demand (|Q| > m), the echoes signal will be transformed into a quasinormal ringdown of the two-way traversable wormhole, and the charged black-bounce is a regular black hole with normal horizons by requiring (|Q| ≤ m) and (|l| < m − m 2 − Q 2 ).

Black bounces in conformal Killing gravity

“…Note that for these three cases described above, the metric function is always positive for r 1 and r 1. In contrast, when analyzing the metric function (23) with > 0, we verify the existence of a broader range of scenarios by varying the mass between M > M c , M = M c and M < M c . In this context, and as before, we assume certain values for the constants, for instance, considering q = 0.5, = 0.2 and λ = 0, the critical mass value is given by M c = 0.764.…”

“…In this reference, an Eddington-Finkelstein coordinate transformation is performed in which the constant mass parameter is now replaced by a dynamic mass that depends on the null temporal coordinate w. The resulting metric is a generalization of the Vaidya metric. One can also replace the constant parameter a by a parameter that depends on the time coordinate w; electrically-charged wormhole and black hole solutions in Einstein-Maxwell-scalar theory, in which the scalar is a phantom field non-minimally coupled to the Maxwell field [10]; the stability of dynamic thin-shell black-bounce traversable wormholes were also explored [11]; the gravitational lensing was analysed in black bounce spacetimes that interpolate between regular black holes and traversable wormholes [12][13][14][15]; a plethora of novel geometries, more complex than before, with two or more horizons, with the possibility of an extremal case were found [7], as well as charged black bounce solutions [16]; observational signatures were also explored [17][18][19][20][21][22][23][24][25]; solutions in NLED and scalar fields were analysed [8,26,27,31]; and black bounce solutions were also studied in several modified theories of gravity [32][33][34], among other topics.…”

(A)dS Taub-NUT and exact black bounces with scalar hair

“…The most obvious, again, black hole thermodynamic since now they represent solutions with a sensible action principle with a clear field content 8 . On the other hand, it is possible to study several astrophysically relevant aspects of these black holes, as for example black hole shadows [75,76], gravitational lensing [77,78], black hole mimickers [79,80], quasinormal modes and echoes [81][82][83][84], to mention a few examples. We expect to report along these lines in our upcoming contributions.…”