Article
Astronomy & Astrophysics
Zeus S. Moreira, Haroldo C. D. Lima Jr, Luis C. B. Crispino, Carlos A. R. Herdeiro
Summary: In this study, we analyze the quasinormal modes (QNMs) of a Schwarzschild black hole with corrections motivated by Loop Quantum Gravity (LQG). The black hole exhibits a global structure of a black bounce, and the QNM frequency orbits in the complex plane are self-intersecting spiraling curves. The overall damping decreases with increasing LQG parameter, and the spectrum of the quantum corrected black hole shows an oscillatory pattern with possible QNMs having vanishing real part.
Article
Astronomy & Astrophysics
Mariano Cadoni, Mauro Oi, Andrea P. Sanna
Summary: By describing the black hole as a statistical ensemble of quantum harmonic oscillators and working in the canonical ensemble, it is shown that in the large-mass black hole limit, the leading contribution to the entropy is the Bekenstein-Hawking term, with a subleading contribution being a logarithmic correction. The number of oscillators is found to scale holographically with the area of the event horizon.
Article
Physics, Particles & Fields
Luis A. H. Mamani, Angel D. D. Masa, Lucas Timotheo Sanches, Vilson T. Zanchin
Summary: In this study, we calculate the quasinormal modes of spin 0, 1/2, 1, 3/2, 2, and 5/2 fields in the asymptotically flat Schwarzschild black hole spacetime using numerical methods. We compare the results with the available literature and test different numerical methods. Additionally, we obtain purely imaginary frequencies for spin 1/2, 3/2, and 5/2 fields, which are consistent with previous analytic results.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
N. Heidari, H. Hassanabadi
Summary: This paper presents a new analytical approach using the Rosen-Morse function to calculate the Quasi Normal Modes (QNMs) of black holes. The proposed method provides a more precise approximation compared to previous methods. The corrected modes based on this research are claimed to be a generalized form of QNMs found by the Posch-Teller function. Numerical results of the new approach are calculated and compared with results obtained by the Mashhoon method and numerical method.
Article
Physics, Multidisciplinary
M. A. Anacleto, J. A. Campos, F. A. Brito, E. Passos
Summary: This study investigates quantum corrections to the Schwarzschild black hole metric using the generalized uncertainty principle (GUP) and explores its effects on quasinormal modes, shadow, and their relationship in the eikonal limit. The research utilizes the sixth-order Wentzel-Kramers-Brillouin (WKB) approximation to calculate quasinormal frequencies and confirms the results through numerical analysis. Interestingly, the shadow radius is found to be nonzero even at very small mass limits for finite GUP parameter.
Article
Astronomy & Astrophysics
Tiago Fernandes, David Hilditch, Jose P. S. Lemos, Vitor Cardoso
Summary: We present new results on the behavior of Proca massive vector fields in a Schwarzschild-anti-de Sitter black hole geometry. The analysis is performed using both vector spherical harmonic decomposition and the Frolov-Krtous-Kubiznak-Santos method. The results show that it is difficult to separate the scalar-type and vector-type polarizations of the electric sector in the vector spherical harmonic method. On the other hand, the Frolov-Krtous-Kubiznak-Santos method captures only two of the three possible polarizations, missing the vector-type magnetic mode sector. The frequencies of the quasinormal modes are carefully computed and compared between the two methods, showing good agreement.
Article
Physics, Particles & Fields
Mengjie Wang, Zhou Chen, Qiyuan Pan, Jiliang Jing
Summary: The study generalizes previous research on Maxwell quasinormal modes around Schwarzschild-anti-de-Sitter black holes by introducing a global monopole and applying Robin-type vanishing energy flux boundary conditions. The Maxwell equations are formulated in two formalisms and solved analytically in pure anti-de Sitter spacetimes with a global monopole, revealing two different normal modes due to the monopole parameter. The Maxwell quasinormal spectrum is analyzed by varying angular momentum quantum number l, overtone number N, and the monopole parameter 8 pi eta 2, demonstrating that the global monopole produces a repulsive force.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Multidisciplinary
Kai Lin, Hongsheng Zhang
Summary: A parametrized Schwarzschild metric (PSM) has been proposed recently to address the differences in mass of M87* from different observations. It was found that the axial gravitational quasinormal modes of this metric are unstable for n > 1. The decay rate of the quasinormal mode is much smaller for n < 1, which can be used to distinguish the PSM from a Schwarzschild metric.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2023)
Article
Physics, Multidisciplinary
Shobhit Giri, Hemwati Nandan, Lokesh Kumar Joshi, Sunil D. Maharaj
Summary: This paper investigates the dynamics of test particles and the stability of circular geodesics in a non-commutative geometry-inspired Schwarzschild black hole spacetime. The study analyzes the Lyapunov exponent and stability of equatorial circular geodesics for both massive and massless test particles, considering different values of the non-commutative parameter (alpha). The instability of null circular orbits is also discussed, and the quasinormal modes for massless scalar field perturbation are evaluated and visualized by relating the angular frequency and Lyapunov exponent.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Astronomy & Astrophysics
Koutarou Kyutoku, Hayato Motohashi, Takahiro Tanaka
Summary: We investigate the scattering of gravitational waves by a Schwarzschild black hole and its perturbed siblings to examine the effect of proposed spectral instability of quasinormal modes on the ringdown signal. Our findings show that the information of dominant ringdown signals, associated with the least damping quasinormal mode of unperturbed Schwarzschild black holes, is imprinted in the phase shift of the transmission amplitude. This behavior is analogous to the resonance of quantum systems being imprinted in the phase shift of the S matrix. The phase shift near the oscillation frequency of the fundamental mode is only perturbatively modified, indicating the stability of the ringdown signal, while the phase shift at low frequencies is significantly modulated due to the late-time excitation of echo signals associated with the destabilized quasinormal-mode spectrum.
Article
Physics, Multidisciplinary
H. Chen, T. Sathiyaraj, H. Hassanabadi, Y. Yang, Z. -W. Long, F. -Q. Tu
Summary: This paper investigates the quasinormal modes of the Schwarzschild black hole under the extended generalized uncertainty principle (EGUP) with the minimal length and momentum. The EGUP-corrected black hole metric function is derived, indicating that quantum effects do not alter the event horizon. The perturbation of the quantum-corrected black hole with scalar and electromagnetic fields is considered, and the effect of quantum correction on the time evolution is analyzed.
INDIAN JOURNAL OF PHYSICS
(2023)
Article
Astronomy & Astrophysics
Che-Yu Chen, Hsu -Wen Chiang, Jie-Shiun Tsao
Summary: This study explores the appearance of eikonal correspondence in asymmetric spacetimes and finds explicit eikonal correspondence in deformed Schwarzschild spacetime.
Article
Astronomy & Astrophysics
Jerzy Matyjasek
Summary: This paper aims to construct accurate frequencies of the quasinormal modes of the five-dimensional Schwarzschild-Tangherlini black hole using three major techniques and discusses the limitations of each. The results show that the Hill determinant method and the continued fractions method often yield identical results, while the WKB-Pade method is remarkably accurate in most cases but may have exceptions. The deviations in frequency accuracy for different perturbations are also analyzed.
Article
Astronomy & Astrophysics
A. Martinez-Merino, M. Sabido
Summary: In this study, the lowest value of black hole spin is investigated using non-extensive entropies. The results show that the spin depends on the area and non-extensive parameter, with the modification only present for micro black holes.
Article
Astronomy & Astrophysics
Hao Chen, Hassan Hassanabadi, Bekir Can Lutfuoglu, Zheng-Wen Long
Summary: Based on the quantum gravity effects and the concepts of minimum measurable momentum, this study examines the Hawking evaporation and stability of black holes. The results show that quantum corrections may shorten the lifetime of black holes, and the effects of the EUP can significantly increase the absorption cross-section of black holes.
GENERAL RELATIVITY AND GRAVITATION
(2022)
Review
Physics, Particles & Fields
Nigel T. Bishop, Luciano Rezzolla
LIVING REVIEWS IN RELATIVITY
(2016)
Article
Astronomy & Astrophysics
Nigel Bishop, Denis Pollney, Christian Reisswig
CLASSICAL AND QUANTUM GRAVITY
(2011)
Article
Astronomy & Astrophysics
Christian Reisswig, Nigel Bishop, Denis Pollney
GENERAL RELATIVITY AND GRAVITATION
(2013)
Article
Astronomy & Astrophysics
Nigel T. Bishop, Christian Reisswig
GENERAL RELATIVITY AND GRAVITATION
(2014)
Article
Astronomy & Astrophysics
Nigel T. Bishop, Petrus J. van der Walt, Monos Naidoo
GENERAL RELATIVITY AND GRAVITATION
(2020)
Article
Astronomy & Astrophysics
Monos Naidoo, Nigel T. Bishop, Petrus J. van der Walt
Summary: The study shows that the claimed GW echoes in LIGO data could not have been caused by matter shells, but in certain scenarios, matter shells can make modifications of a few percent to GW signals.
GENERAL RELATIVITY AND GRAVITATION
(2021)
Article
Astronomy & Astrophysics
Nigel T. Bishop, Petrus J. Walt, Monos Naidoo
Summary: This paper investigates the damping effect of gravitational waves (GWs) propagating through a viscous fluid, particularly in core collapse supernovae (CCSNe). The study shows that the damping effect is significant when the wavelength is much larger than the inner radius of the matter shell. The research also finds that significant damping occurs in CCSNe and primordial gravitational waves generated during inflation in the early Universe.
Article
Astronomy & Astrophysics
Thanasis Giannakopoulos, Nigel T. Bishop, David Hilditch, Denis Pollney, Miguel Zilhao
Summary: This article explores the application of the characteristic initial (boundary) value problem in general relativity and reveals that several prototype formulations using Bondi-like coordinates exhibit weak hyperbolicity. The root cause and potential solutions to this issue are discussed, and the impact of weak hyperbolicity in practice is demonstrated through numerical convergence tests.
Article
Physics, Multidisciplinary
Amos S. Kubeka, Nigel T. Bishop
INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS
(2008)
Article
Astronomy & Astrophysics
NT Bishop, R Gómez, L Lehner, M Maharaj, J Winicour
Article
Astronomy & Astrophysics
NT Bishop, F Beyer, M Koppitz
Article
Astronomy & Astrophysics
NT Bishop, R Gómez, S Husa, L Lehner, J Winicour
