Gravitational Lens Effect of a Moving Black Hole

1976 ◽  
Vol 3 (1) ◽  
pp. 42-43
Author(s):  
Z. Kvíz
Keyword(s):  
Black Hole ◽  
Gravitational Field ◽  
Gravitational Lens ◽  
Nearby Star ◽  
Lens Effect ◽  
Distant Star ◽  
Light Rays

The deflection of the light rays of a distant star by the gravitational field of a nearby star was first derived independently by Link (1936) and Einstein (1936). It was shown by Link (1936,1937) that the light of a distant star is not only deflected forming two separate images of the distant star, but also the brightness of the distant star (in both images) is affected.

The Schwarzschild black hole

2018 ◽  
Author(s):  
Nathalie Deruelle ◽  
Jean-Philippe Uzan
Keyword(s):  
Black Hole ◽  
Gravitational Field ◽  
Equilibrium Configuration ◽  
Original Form ◽  
Schwarzschild Black Hole ◽  
Schwarzschild Metric ◽  
Schwarzschild Geometry

This chapter discusses the Schwarzschild black hole. It demonstrates how, by a judicious change of coordinates, it is possible to eliminate the singularity of the Schwarzschild metric and reveal a spacetime that is much larger, like that of a black hole. At the end of its thermonuclear evolution, a star collapses and, if it is sufficiently massive, does not become stabilized in a new equilibrium configuration. The Schwarzschild geometry must therefore represent the gravitational field of such an object up to r = 0. This being said, the Schwarzschild metric in its original form is singular, not only at r = 0 where the curvature diverges, but also at r = 2m, a surface which is crossed by geodesics.

Gravitational Lens Effect: An Observational Test

Science ◽  
1966 ◽  
Vol 151 (3706) ◽  
pp. 73-74 ◽  
Author(s):  
W. A. Feibelman
Keyword(s):  
Gravitational Lens ◽  
Lens Effect ◽  
Observational Test

A diffraction limit on the gravitational lens effect

1981 ◽  
Vol 78 (1) ◽  
pp. 199-210 ◽  
Author(s):  
Robert J. Bontz ◽  
Mark P. Haugan
Keyword(s):  
Diffraction Limit ◽  
Gravitational Lens ◽  
Lens Effect

scholarly journals ISSUE ON MEASURING THE LIGHT SPEED IN VACUUM

2021 ◽  
Vol 82 (4) ◽  
pp. 61-64
Author(s):  
Vasil Сhaban ◽  
Keyword(s):  
Gravitational Field ◽  
Differential Equations ◽  
Gravitational Lens ◽  
Electric Signal ◽  
The Sun ◽  
Speed Of Light ◽  
Light Speed ◽  
Shapiro Effect

Based on the proposed differential equations of the interaction of the electric signal with the gravitational field, the observed phenomena are known as the gravitational lens and the Shapiro effect are investigated. The deflection of a light ray in the field of the Sun is simulated. It is shown that a moving photon undergoes in the gravitational field not only a transverse action, which causes a curvature of the trajectory but also a longitudinal one, implementing the acceleration-braking processes. As a result, the instability of the speed of light in a vacuum was revealed.

Is there any gravitational field outside a black hole?

1978 ◽  
Vol 23 (11) ◽  
pp. 409-412 ◽  
Author(s):  
V. De Sabbata ◽  
K. Tahik Shah
Keyword(s):  
Black Hole ◽  
Gravitational Field

Bound orbits around modified Hayward black holes

2021 ◽  
Author(s):  
Bo Gao ◽  
Xue-Mei Deng
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Angular Momentum ◽  
Gravitational Field ◽  
Periodic Orbits ◽  
Kerr Black Hole ◽  
Periodic Oscillations ◽  
Test Particles ◽  
Spin Parameter ◽  
Bound Orbits

The neutral time-like particle’s bound orbits around modified Hayward black holes have been investigated. We find that both in the marginally bound orbits (MBO) and the innermost stable circular orbits (ISCO), the test particle’s radius and its angular momentum are all more sensitive to one of the parameters [Formula: see text]. Especially, modified Hayward black holes with [Formula: see text] could mimic the same ISCO radius around the Kerr black hole with the spin parameter up to [Formula: see text]. Small [Formula: see text] could mimic the ISCO of small-spinning test particles around Schwarzschild black holes. Meanwhile, rational (periodic) orbits around modified Hayward black holes have also been studied. The epicyclic frequencies of the quasi-circular motion around modified Hayward black holes are calculated and discussed with respect to the observed Quasi-periodic oscillations (QPOs) frequencies. Our results show that rational orbits around modified Hayward black holes have different values of the energy from the ones of Schwarzschild black holes. The epicyclic frequencies in modified Hayward black holes have different frequencies from Schwarzschild and Kerr ones. These might provide hints for distinguishing modified Hayward black holes from Schwarzschild and Kerr ones by using the dynamics of time-like particles around the strong gravitational field.

Sign in / Sign up

Export Citation Format

Share Document