Scattering of massless scalar waves by a Schwarzschild black hole: A phase-integral study

1995 ◽  
Vol 52 (4) ◽  
pp. 1808-1820 ◽  
Author(s):  
Nils Andersson
Keyword(s):  
Black Hole ◽  
Massless Scalar ◽  
Schwarzschild Black Hole ◽  
Phase Integral ◽  
Scalar Waves

scholarly journals High-dimensional Schwarzschild black holes in scalar–tensor–vector gravity theory

2021 ◽  
Vol 81 (6) ◽  
Author(s):  
Xin-Chang Cai ◽  
Yan-Gang Miao
Keyword(s):  
Black Hole ◽  
Black Hole Solution ◽  
Emission Rate ◽  
Null Geodesic ◽  
High Dimensional ◽  
Massless Scalar ◽  
Massless Scalar Field ◽  
Spacetime Dimension ◽  
Schwarzschild Black Hole ◽  
Scalar Waves

AbstractWe obtain a high-dimensional Schwarzschild black hole solution in the scalar–tensor–vector gravity (STVG), and then analyze the influence of parameter $$\alpha $$ α associated with a deviation of the STVG theory from General Relativity on event horizons and Hawking temperature. We calculate the quasinormal mode frequencies of massless scalar field perturbations for the high-dimensional Schwarzschild STVG black hole by using the sixth-order WKB approximation method and the unstable null geodesic method in the eikonal limit. The results show that the increase of parameter $$\alpha $$ α makes the scalar waves decay slowly, while the increase of the spacetime dimension makes the scalar waves decay fast. In addition, we study the influence of parameter $$\alpha $$ α on the shadow radius of this high-dimensional Schwarzschild STVG black hole and find that the increase of parameter $$\alpha $$ α makes the black hole shadow radius increase, but the increase of the spacetime dimension makes the black hole shadow radius decrease. Finally, we investigate the energy emission rate of the high-dimensional Schwarzschild STVG black hole, and find that the increase of parameter $$\alpha $$ α makes the evaporation process slow, while the increase of the spacetime dimension makes the process fast.

scholarly journals Black hole S-matrix for a scalar field

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Panos Betzios ◽  
Nava Gaddam ◽  
Olga Papadoulaki
Keyword(s):  
Black Hole ◽  
Normal Modes ◽  
Massless Scalar ◽  
Scattering Process ◽  
Schwarzschild Black Hole ◽  
Asymptotically Flat ◽  
Scalar Particles ◽  
Black Hole Background ◽  
S Matrix ◽  
Do So

Abstract We describe a unitary scattering process, as observed from spatial infinity, of massless scalar particles on an asymptotically flat Schwarzschild black hole background. In order to do so, we split the problem in two different regimes governing the dynamics of the scattering process. The first describes the evolution of the modes in the region away from the horizon and can be analysed in terms of the effective Regge-Wheeler potential. In the near horizon region, where the Regge-Wheeler potential becomes insignificant, the WKB geometric optics approximation of Hawking’s is replaced by the near-horizon gravitational scattering matrix that captures non-perturbative soft graviton exchanges near the horizon. We perform an appropriate matching for the scattering solutions of these two dynamical problems and compute the resulting Bogoliubov relations, that combines both dynamics. This allows us to formulate an S-matrix for the scattering process that is manifestly unitary. We discuss the analogue of the (quasi)-normal modes in this setup and the emergence of gravitational echoes that follow an original burst of radiation as the excited black hole relaxes to equilibrium.

scholarly journals NUMERICAL SIMULATION OF QUASI-NORMAL MODES IN TIME-DEPENDENT BACKGROUND

2004 ◽  
Vol 19 (03) ◽  
pp. 239-252 ◽  
Author(s):  
LI-HUI XUE ◽  
ZAI-XIONG SHEN ◽  
BIN WANG ◽  
RU-KENG SU
Keyword(s):  
Numerical Simulation ◽  
Black Hole ◽  
Wave Propagation ◽  
Normal Modes ◽  
Time Dependent ◽  
Massless Scalar ◽  
Scalar Wave ◽  
Schwarzschild Black Hole ◽  
Black Hole Background ◽  
Scattering Potential

We study the massless scalar wave propagation in the time-dependent Schwarzschild black hole background. We find that the Kruskal coordinate is an appropriate framework to investigate the time-dependent spacetime. A time-dependent scattering potential is derived by considering dynamical black hole with parameters changing with time. It is shown that in the quasinormal ringing both the decay time-scale and oscillation are modified in the time-dependent background.

scholarly journals Massive scalar field quasinormal modes of a Schwarzschild black hole surrounded by quintessence

Open Physics ◽  
2008 ◽  
Vol 6 (2) ◽  
Author(s):  
Chunrui Ma ◽  
Yuanxing Gui ◽  
Wei Wang ◽  
Fujun Wang
Keyword(s):  
Black Hole ◽  
Scalar Field ◽  
Quasinormal Modes ◽  
Massless Scalar ◽  
Massless Scalar Field ◽  
Massive Scalar ◽  
Schwarzschild Black Hole ◽  
Third Order ◽  
Massive Scalar Field ◽  
Absolute Value

AbstractWe present the quasinormal frequencies of the massive scalar field in the background of a Schwarzchild black hole surrounded by quintessence with the third-order WKB method. The mass of the scalar field u plays an important role in studying the quasinormal frequencies, the real part of the frequencies increases linearly as mass of the field u increases, while the imaginary part in absolute value decreases linearly which leads to damping more slowly than the massless scalar field. The frequencies have a limited value, so it is easier to detect the quasinormal modes. Moreover, owing to the presence of the quintessence, the massive scalar field damps more slowly.

scholarly journals Scattering by regular black holes: Planar massless scalar waves impinging upon a Bardeen black hole

2015 ◽  
Vol 92 (2) ◽  
Author(s):  
Caio F. B. Macedo ◽  
Ednilton S. de Oliveira ◽  
Luís C. B. Crispino
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Massless Scalar ◽  
Regular Black Holes ◽  
Scalar Waves

scholarly journals Distinguishing black holes through their ringing

SURG Journal ◽  
2010 ◽  
Vol 4 (1) ◽  
pp. 87-92
Author(s):  
Shannon Potter ◽  
Luis Lehner
Keyword(s):  
Black Hole ◽  
Gravitational Wave ◽  
Black Hole Solution ◽  
Alternative Explanation ◽  
Quasinormal Modes ◽  
Massless Scalar ◽  
Massless Scalar Field ◽  
Schwarzschild Black Hole ◽  
Black Hole Spacetime ◽  
Hole Model

A perturbed black hole spacetime emits gravitational waves possessing quasinormal modes that are characteristic of the black hole itself. We use a massless scalar field as an analog to a gravitational wave to find the quasinormal modes emitted by both a Schwarzschild black hole and a new alternative black hole model which places the Schwarzschild black hole in an aether—a zero density, negative pressure perfect fluid. The later model was proposed as an alternative explanation for accelerated cosmic expansion [1]. We construct a computational code to study both systems numerically and obtain the corresponding quasinormal modes. We find that the quasinormal modes of a black hole in an aether are distinguishable from those of a Schwarzschild black hole and so, in principle, gravitational wave observations could be exploited to determine if either black hole solution represents those existing in our universe.

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