scholarly journals Photon escape in the extremal Kerr black hole spacetime

2022 ◽  
Vol 105 (2) ◽  
Author(s):  
Kota Ogasawara ◽  
Takahisa Igata
2018 ◽  
Vol 33 (23) ◽  
pp. 1850126
Author(s):  
Ravi Shankar Kuniyal ◽  
Hemwati Nandan ◽  
Uma Papnoi ◽  
Rashmi Uniyal ◽  
K. D. Purohit

We study the motion of massless test particles in a five-dimensional (5D) Myers–Perry black hole spacetime with two-spin parameters. The behavior of the effective potential in view of different values of black hole parameters is discussed in the equatorial plane. The frequency shift of photons is calculated which is found to depend on the spin parameter of black hole and the observed redshift is discussed accordingly. The deflection angle and the strong deflection limit coefficients are also calculated and their behavior with the spin parameters is analyzed in detail. It is observed that the behaviors of both deflection angle and strong field coefficient differs from Kerr black hole spacetime in four dimensions in General Relativity (GR), which is mainly due to the presence of two-spin parameters in higher dimension.


2021 ◽  
Vol 81 (3) ◽  
Author(s):  
Xuan Zhou ◽  
Songbai Chen ◽  
Jiliang Jing

AbstractWe present firstly the equation of motion for the test scalar particle coupling to the Chern–Simons invariant in Kerr black hole spacetime by the short-wave approximation. We have analyzed the dynamical behaviors of the test coupled particles by applying techniques including Poincaré sections, fast Lyapunov exponent indicator, bifurcation diagram and basins of attraction. It is shown that there exists chaotic phenomenon in the motion of scalar particle interacted with the Chern–Simons invariant in a Kerr black hole spacetime. With the increase of the coupling strength, the motion of the coupled particles for the chosen parameters first undergoes a series of transitions betweens chaotic motion and regular motion and then falls into horizon or escapes to spatial infinity. Thus, the coupling between scalar particle and Chern–Simons invariant yields the richer dynamical behavior of scalar particle in a Kerr black hole spacetime.


Sign in / Sign up

Export Citation Format

Share Document