Quasinormal modes of black holes in f(T) gravity

Abstract

We calculate the quasinormal modes (QNM) frequencies of a test massless scalar field and an electromagnetic field around static black holes in f(T) gravity. Focusing on quadratic f(T) modifications, which is a good approximation for every realistic f(T) theory, we first extract the spherically symmetric solutions using the perturbative method, imposing two ansätze for the metric functions, which suitably quantify the deviation from the Schwarzschild solution. Moreover, we extract the effective potential, and then calculate the QNM frequency of the obtained solutions. Firstly, we numerically solve the Schrödinger-like equation using the discretization method, and we extract the frequency and the time evolution of the dominant mode applying the function fit method. Secondly, we perform a semi-analytical calculation by applying the WKB method with the Pade approximation. We show that the results for f(T) gravity are different compared to General Relativity, and in particular we obtain a different slope and period of the field decay behavior for different model parameter values. Hence, under the light of gravitational-wave observations of increasing accuracy from binary systems, the whole analysis could be used as an additional tool to test General Relativity and examine whether torsional gravitational modifications are possible.

Black hole shadow and chaos bound violation in f(T) teleparallel gravity

“…Other modifications on QNMs in f (T )-gravity have been recently studied in Ref. [36] for spherically static symmetric solutions. In our case, we consider the leading order modifications from a dynamical horizon.…”

Gravitational traces of bumblebee gravity in metric–affine formalism

“…The investigation of quasinormal modes of black holes has extensively utilized the weak field approximation in the literature, both in general relativity (GR) [42,[44][45][46][47][48][49][50][51][52][53][54][55][56][57] and in alternative gravity theories such as Ricci-based theories [58][59][60], Lorentz violation [61,62], and related fields [32,[63][64][65][66].…”

General effective field theory of teleparallel gravity

“…Since torsional gravity gives rises to novel modified gravity theories, that cannot arise in the curvature framework, it has attracted the interest of the literature [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57]. Nevertheless, despite the significant research on torsional gravity, the formulation of an effective field theory (EFT) has not been investigated in full detail (see [58] where the EFT approach of torsional gravity around a cosmological background is presented, and [59] where one-loop corrections are explored in the context of teleparallel renormalization).…”