Gravitational signatures of a nonlinear electrodynamics in $f(R,T)$ gravity

TL;DR

This paper explores the effects of nonlinear electrodynamics within $f(R,T)$ gravity on black hole properties, including horizons, shadows, thermodynamics, quasinormal modes, and gravitational lensing, constrained by observational data.

Contribution

It introduces a novel analysis of nonlinear electrodynamics in $f(R,T)$ gravity, linking theoretical predictions with observational constraints from EHT data.

Findings

Constraints on parameters $eta$ and $eta$ from EHT data.

Detailed characterization of black hole shadows and photon spheres.

Analysis of quasinormal modes and thermodynamic stability.

Abstract

In this work, we investigate a nonlinear electrodynamics model within the framework of $f(R,T)$ gravity. We begin by outlining the general features of the theory and analyzing the event horizon under conditions ensuring its real and positive definiteness. We then examine light trajectories, focusing on critical orbits, shadow radii, and geodesics of massless particles. The parameters $\alpha$ and $\beta$, associated with the nonlinear extension of the Reissner-Nordstr\"om spacetime, are constrained using observational data from the Event Horizon Telescope (EHT). Subsequently, we analyze the thermodynamic properties of the system, including Hawking temperature, entropy, and heat capacity. Quasinormal modes are computed for scalar, vector, tensor, and spinorial perturbations, with the corresponding time-domain profiles explored as well. Gravitational lensing is then studied in both weak and strong deflection limits, along with the stability of photon spheres. Finally, we examine additional topological aspects, including topological thermodynamics and the topological photon sphere.