Study of the Deflection Angle and Shadow of Black Hole Solutions in Non‐Plasma and Plasma Mediums Under the Effect of Einstein–Gauss–Bonnet Gravity

Abstract

AbstractIn this paper, the Gibbons and Werner technique is used to calculate the weak deflection angle for the black hole solution under the effects of Einstein–Gauss–Bonnet gravity. The Gauss–Bonnet theorem in the limits of weak field is used to evaluate the Gaussian optical curvature in order to obtain the results. The visual effects of the deflection angle on the impact parameter is also looked at and the smallest radius in the non‐plasma/plasma medium. Moreover, in order to check the consistency of the results concerning the weak deflection angle, the Keeton and Petters approach is applied to study the deflection angle, which is the expansion of series with a single mass variable, which can be directly addressed by using the post–post Newtonian framework. Furthermore, the deflection angle and shadow under the influence of the plasma is examined by using the motion of particle in a non‐magnetized plasma and pressure‐free plasma medium as described by the new ray‐tracing algorithm. It is shown that plasma as well as Einstein–Gauss‐Bonnet gravity corrections are affected by shadows.