Gravitational lensing for Simple Black Holes with Anisotropic Fluid

This paper explores gravitational lensing and photon dynamics around black holes surrounded by anisotropic fluids, described by a spacetime metric incorporating mass M and an anisotropy parameter K. We analyze the horizon structure for three distinct cases of the equation-of-state parameter omega_2 (dust, radiation, and dark energy-like), revealing how each modifies the black hole geometry. Using the Hamilton-Jacobi formalism, we derive equations of motion for photons in the presence of plasma, examining photon spheres and shadow formation. Our study includes weak gravitational lensing effects for both uniform and non-uniform plasma distributions, demonstrating how plasma frequency and spacetime parameters influence light deflection. Numerical results illustrate the dependence of deflection angles on the impact parameter and anisotropic fluid properties. The findings highlight the role of anisotropic matter in altering observable phenomena such as shadows and lensing patterns, providing insights into testing strong-field gravity with future astrophysical observations.

Hali tarjima qilinmagan