Testing metric-affine gravity using particle dynamics and photon motion

Abstract

This work mainly focuses to unveil the optical features of a black hole. For this objective, we utilize the metric-affine black hole geometry, including dilation, spin, and shear charge. The Lagrangian coefficients f1 and d1 are the main parameters that differentiate the solutions by d1=±8f1, where f1<0. Based on these parameters, we carry out this work in two cases, i.e., d1=8f1,&d1=−8f1. We forecast the detailed impact of dilation, spin, and shear charges on the optical properties of black hole in both cases. To reveal the optical features, we calculate horizon radius, inner stable circular orbit, photon sphere radius, BH shadows, quasi-periodic oscillations, the red-blue shift of photon particles, effective force, weak gravitational lensing, and image magnification by using metric-affine gravity black hole geometry.