Deriving Weak Deflection Angle by Black Holes or Wormholes using Gauss-Bonnet Theorem

Abstract

In this review, various researches on finding the bending angle of light deflected by a massive gravitating object which regard the Gauss-Bonnet theorem as the premise have been revised. Primarily, the Gibbons and Werner method is studied apropos of the gravitational lensing phenomenon in the weak field limits. Some exclusive instances are deliberated while calculating the deflection angle, beginning with the finite-distance corrections on non-asymptotically flat spacetimes. Effects of plasma medium is then inspected to observe its contribution to the deflection angle. Finally, the Jacobi metric is explored as an alternative method, only to arrive at similar results. All of the cases are probed in three constructs, one as a generic statement of explanation, one for black holes, and one for wormholes, so as to gain a perspective on every kind of influence.

Weak Deflection Angle and Greybody Bound of Magnetized Regular Black Hole

“…Crisnejo and Gallo [21] investigated the deflection angle of light in plasma medium. Since then, there has been a constantly increasing interest in the WGL through the Gibbons and Werner technique using GBT methodology for BHs and wormholes [22][23][24][25][26][27][28][29]. In addition, Hensh et al [30] computed the GL of Kehagias-Sfetsos compact objects surrounded by plasma.…”