Sixteenth Marcel Grossmann Meeting

Gravitational lensing by rotating Simpson--Visser black holes

9 Jul 2021, 07:30

20m

Talk in the parallel session Gravitational Lensing and Shadows Gravitational Lensing and Shadows

Speaker

Sushant Ghosh (Jamia millia Islamia)

Description

We investigate strong-field gravitational lensing by rotating Simpson-Visser black hole, which has an additional parameter ($l$), apart from mass ($M$) and rotation parameter ($a$). It can admit Cauchy and event horizons for some parameters and free from the singularity and assess phenomenological differences from the Kerr black holes. We also find a decrease in the deflection angle ${\alpha }_D$, angular position ${\theta }_1$ decreases more slowly and $x_m$ more quickly, but angular separation $s$ increases more rapidly, and their behavior is similar to that of the Kerr black hole. We apply the formalism to discuss the astrophysical consequences in the supermassive black holes NGC 4649, NGC 1332, Sgr A and M87 and find that the rotating Simpson-Visser black holes can be quantitatively distinguished from the Kerr black hole via gravitational lensing effects. However, the deviations of the angular positions of the first image from that of the Kerr black hole are not more than $0.194\mu$as for Sgr A*, $0.04565\mu$as for M87, $0.0920051\mu$as for NGC 4649, and $0.0487413\mu$as for NGC 1332 and thus required resolution is much higher than current astronomical observation capability like of EHT.

Proceedings

Paper

RSVRevised.pdf