Article
Astronomy & Astrophysics
Saeedeh Sadeghian, Hovhannes Demirchian
Summary: The separability of the Klein-Gordon equation near the horizon of a rotating Myers-Perry black hole in d dimensions is investigated in two limits: generic extremal case and extremal vanishing horizon case. The temperature of the black hole vanishes in the generic extremal case due to a relation between mass and rotation parameters, while in the extremal vanishing horizon case, one rotation parameter is restricted to zero on top of the extremality condition. The Klein-Gordon equation is shown to be separable in both cases, with the radial part of the equation being solved and its behavior discussed in small- and large-r regions.
Article
Astronomy & Astrophysics
Lam Hui, Y. . T. Albert Law, Luca Santoni, Guanhao Sun, Giovanni Maria Tomaselli, Enrico Trincherini
Summary: Studies on black hole superradiance often focus on the growth of a cloud in isolation and the spin-down of the black hole. However, this paper considers the additional effect of matter and angular momentum accretion from the surrounding environment. The authors demonstrate that the black hole can evolve by drifting along the superradiance threshold, allowing for analytical or semi-analytical description of its parameter evolution. They also propose the concept of oversuperradiance, where accretion effectively feeds the superradiance cloud through the black hole. Two examples of accretion processes are provided: from a vortex in wave dark matter and from a baryonic disk. The paper also discusses level transition in a similar manner.
Article
Astronomy & Astrophysics
Bogeun Gwak
Summary: We investigate the weak cosmic censorship conjecture in Myers-Perry black holes in general dimensions using the scattering of a massless scalar field. By analyzing the fluxes of the scalar field into the black hole and the changes in mass and angular momenta of the black hole, we find that the conjecture holds true. Moreover, the changes in the black hole are also examined from a thermodynamic perspective, which further supports the conjecture.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Physics, Multidisciplinary
Qanitah Ama-Tul-Mughani, Arfa Waseem, Wardat Us Salam, Abdul Jawad
Summary: This paper investigates the greybody factor and thermodynamic properties of rotating and regular black holes in the vicinity of perfect fluid dark matter. By converting equations and performing calculations, it is concluded that the attractiveness of the black hole decreases, leading to a decrease in the greybody factor, as the rotation parameter and strength of the dark matter reduce. The entropy of the black hole is also found to increase with larger values of the rotation parameter.
CHINESE JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
Zhi-Wen Lin, Yu Zhang, Qian Li, Chen Ma, Peng-Fei Duan
Summary: This paper investigates the temperature and entropy of a magnetic black hole in the four-dimensional ESTGB theory and explores the effects of generalized uncertainty principle (GUP) on its standard thermodynamics. The study reveals that GUP plays an important role in the final stage of black hole evaporation, with observed logarithmic correction of entropy, remnants, and phase transition phenomena.
INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS
(2022)
Article
Physics, Nuclear
Zhi-Wen Lin, Chen Ma, Yu Zhang, Qian Li, Peng-Fei Duan
Summary: This paper investigates the effects of the generalized uncertainty principle (GUP) on Hawking radiation of scalar particles and fermions tunneling of the Babichev-Charmousis black hole. By modifying the Klein-Gordon equation and Dirac equation, the corrected Hawking temperature and thermodynamic quantities are derived. It is found that the corrected temperature depends on the GUP parameter and there exist minimum mass and minimum entropy.
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
(2022)
Article
Physics, Particles & Fields
Behnam Pourhassan, Salman Sajad Wani, Saheb Soroushfar, Mir Faizal
Summary: This paper obtains quantum work for a quantum scale five dimensional Myers-Perry black hole, showing that at small quantum scales, the quantum work is corrected by non-perturbative quantum gravitational corrections which also alter the stability of the black hole. Multiple quantum corrected effective information metrics are used to analyze the stability of the quantum Myers-Perry black hole.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Mathematics
Jeronimo Cortez, Beatriz Elizaga Navascues, Guillermo A. Mena Marugan, Alvaro Torres-Caballeros, Jose Velhinho
Summary: This study focuses on the canonical quantization of a scalar field in Kantowski-Sachs spacetime. The quantization method, involving a time-dependent canonical transformation and the preservation of spatial symmetries, is shown to be unique and compatible with quantum unitary dynamics and classical symmetries. The findings have implications not only in cosmological applications but also in understanding the interior geometry of nonrotating black holes.
Article
Materials Science, Multidisciplinary
C. P. Onyenegecha, A. I. Opara, I. J. Njoku, S. C. Udensi, U. M. Ukewuihe, C. J. Okereke, A. Omame
Summary: Approximate solutions to the Klein-Gordon equation with the modified Mobius squared potential were obtained using the Nikiforov-Uvarov (NU) method, resulting in relativistic energy eigenvalues and corresponding wave functions. It was demonstrated that in the non-relativistic limit, the energy eigenvalues converge to those of the Schrödinger equation. The behavior of CO, NO, and HCl molecules under the influence of the modified Mobius squared potential was investigated, with numerical values of energies for arbitrary quantum numbers presented.
RESULTS IN PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
A. Dhahbi, A. A. Landolsi
Summary: Using an improved Greene-Aldrich approximation scheme, this paper solves the D-dimensional Klein-Gordon equation with equal scalar and vector Bargmann potentials and non-zero angular momentum number. The equation provides the bound-state energy eigenvalues and the corresponding normalized radial wave functions. The study also discusses the cases of Hulten and Yukawa potentials and analyzes the behavior of energy levels with the parameters of the Bargmann potential.
RESULTS IN PHYSICS
(2022)
Article
Astronomy & Astrophysics
Rong-Zhen Guo, Chen Yuan, Qing-Guo Huang
Summary: In this paper, the effects of near-horizon microstructure on superradiant instabilities of black holes are explored. The results imply that the evolution of a boson-black hole system and the gravitational waves it emits would be influenced by the near-horizon physics of a black hole.
Article
Physics, Multidisciplinary
Seema Rawat
Summary: A pure quaternionic Klein-Gordon equation is developed, emphasizing the superiority of quaternion representation in relativistic quantum mechanics. The equation of continuity in quaternion space is obtained, applicable to both particles and antiparticles, and hinting towards new particles, dark matter, or new physical phenomena. Furthermore, a pure quaternionic generalized Klein-Gordon equation for massless and massive dyons and monopoles in the electromagnetic field is formulated.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Materials Science, Multidisciplinary
Mohammad Partohaghighi, Zahrasadat Mirtalebi, Ali Akgul, Muhammad Bilal Riaz
Summary: This article introduces a new type of fractional Klein-Gordon problem and solves it numerically. Using operational matrix technique and basic functions, the approximate solutions of the problem are obtained, and the numerical results and errors are shown through graphs.
RESULTS IN PHYSICS
(2022)
Article
Physics, Multidisciplinary
Djahid Bouchefra, Badredine Boudjedaa
Summary: This paper calculates the bound state solutions and energy eigenvalues of the Dirac equation with non-central scalar and vector potentials using a modified double ring-shaped generalized Cornell potential in the framework of quasi-exactly solvable problems. When spin symmetry is present, the Dirac equation is transformed into a Schrodinger-like equation, with the angular parts of the solutions computed using functional Bethe ansatz and the radial part determined by solving the biconfluent Heun differential equation.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Astronomy & Astrophysics
Ronaldo Thibes
Summary: This paper introduces a natural family of higher-order partial differential equations by generalizing the second-order Klein-Gordon equation. The associated model is characterized by a generalized action for a scalar field with higher-derivative terms, and the limit obtained from higher-order powers of the d'Alembertian operator is discussed. The general model is constructed using the exponential of the d'Alembertian differential operator, and canonical energy-momentum tensor densities and field propagators are explicitly computed for both homogeneous and non-homogeneous situations, resulting in classical solutions for all cases.
MODERN PHYSICS LETTERS A
(2021)
Article
Physics, Mathematical
Faisal Javed, G. Fatima, G. Mustafa, Ali Ovgun
Summary: This paper investigates the stable configuration of thin-shell wormholes formed from two equivalent geometries of Reissner-Nordstrom black hole with nonlinear electrodynamics. The stability of the developed model is explored by considering different types of matter distribution located at thin-shell. It is found that the presence of nonlinear electrodynamics allows for stable regions in the Reissner-Nordstrom black hole.
INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Reggie C. Pantig, Ali Ovgun
Summary: In this paper, the Poincare Gauge theory of gravity is used to analyze the effects of torsion on black holes by studying the deflection angles and shadow radius. The study also explores the impact of torsion on the luminosity of the photonsphere and other properties of black holes. The findings suggest that the torsion parameter plays a significant role in these phenomena.
Article
Physics, Multidisciplinary
Reggie C. Pantig, Ali Ovgun
Summary: In this work, the researchers investigated the impact of fuzzy dark matter (FDM) or wave dark matter on a supermassive black hole (SMBH). By treating the FDM as a spherical distribution surrounding the SMBH, they obtained a new metric that combines the black hole and dark matter spacetime geometries. The study also analyzed the effects of soliton dark matter on the shadow behavior and weak deflection angle, and found considerable deviations that suggest the possible experimental detection of soliton dark matter using an SMBH at the galactic centers.
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2023)
Article
Physics, Mathematical
Wajiha Javed, Mehak Atique, Reggie C. Pantig, Ali Ovgun
Summary: This paper investigates gravitational lensing in the weak field limits and shadows of charged black holes in non-linear electrodynamics corrections. The results show that the bending angle increases with the effects of mediums in vacuum and plasma, and exponentially decreases with the impact parameter u.
INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Amodio Carleo, Gaetano Lambiase, Ali Ovgun
Summary: Non-linear electrodynamics is a generalization of Maxwell's electrodynamics for strong fields, with significant implications for black hole and cosmology studies. Two new methods for investigating these non-linear theories are explored in this study. The Blandford-Znajek mechanism is analyzed, revealing that the emitted power can increase or decrease depending on the NLED model, and the black hole's magnetic field lines become vertical quickly. The confinement of NLED parameters by amplifying primordial magnetic fields is attempted, proving useful only in certain models.
ANNALEN DER PHYSIK
(2023)
Article
Physics, Mathematical
Abdul Jawad, Shahid Chaudhary, Muhammad Yasir, Ali Ovgun, Izzet Sakalli
Summary: In this paper, the spectrum of the quasinormal modes of Hayward black hole in Einstein-Gauss-Bonnet gravity, Hayward black hole in anti-de Sitter space (AdS) spacetime, and 4-dimensional black hole in Einstein-Lovelock gravity is evaluated. The 6th-order WKB resonance technique is used to examine the quasinormal modes frequencies ? by shifting the charge parameter Q, circular harmonic index l, and mass of scalar field m. It is observed that the 6th-order WKB method gives high accuracy when the multipole number l is larger than the overtone n. The real and imaginary components of the quasinormal modes are not linear functions, similar to Reisnner-Nordstrom-AdS. For large values of charge, the quasinormal ringing becomes slower and the frequency of the oscillation becomes smaller.
INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
(2023)
Article
Physics, Multidisciplinary
M. Umair Shahzad, Aqsa Mehmood, Sana Sharif, Ali Ovgun
Summary: This work investigates the thermodynamics, phase transition, and topological classes of Neutral Gauss-Bonnet AdS black holes in 5D. The study explores the thermodynamic properties and stability of the black holes through graphical analysis, and discusses the topology of the thermodynamic critical points.
Article
Physics, Multidisciplinary
Anshuman Baruah, Ali Ovgun, Atri Deshamukhya
Summary: In this study, we investigate the quasinormal modes (QNMs) of modified black holes in non-minimally coupled Kalb-Ramond (KR) gravity. We use the generalized uncertainty principle (GUP) to account for quantum corrections, and find that the Lorentz violating parameters in the model influence the QNM frequencies and depend on the GUP parameters.
Article
Astronomy & Astrophysics
Ilim Irfan cimdiker, Ali Ovgun, Durmus Demir
Summary: In this study, we investigate circular orbits, effective potential, and thin-accretion disk of a black hole in symmergent gravity (SG), using the Novikov-Thorne model and considering the energy flux and temperature distribution. We establish limits on SG parameters and conclude that the accretion disk can serve as an astrophysical tool for probing SG.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Beyhan Pulice, Reggie C. Pantig, Ali Ovgun, Durmus Demir
Summary: In this paper, the authors report on exact charged black hole solutions in symmergent gravity with a Maxwell field. They study various properties of the black holes, such as horizon formation, shadow cast, and gravitational lensing, as functions of the black hole charge. They also explore the weak field regime and discuss the potential detectability of a weak deflection angle caused by the black hole.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Wajiha Javed, Mehak Atique, Ali Ovguen
Summary: In this paper, the weak deflection angle of electric and magnetic black holes in the background of nonlinear electrodynamics is studied using the Gauss-Bonnet theorem and bounding greybody factor. The Gaussian optical curvature is obtained using the approach of Gibbons and Werner, and then used in the Gauss-Bonnet theorem to calculate the bending angle. The rigorous bounds of the greybody factor are also calculated, and the graphical behavior of bending angles and greybody bounds at specific values of parameters and black hole charges is analyzed.
Article
Physics, Particles & Fields
Dhruba Jyoti Gogoi, Ali Ovgun, M. Koussour
Summary: In this work, we studied the quasinormal modes of a black hole in f(Q) Sigma nin f(Q) gravity using the Bernstein spectral method, and validated the method with the Pade averaged higher-order WKB approximation method. We considered scalar and electromagnetic perturbations in the black hole spacetime and obtained the corresponding quasinormal modes. We found that the quasinormal frequencies in scalar perturbation are higher than those in electromagnetic perturbation for a non-vanishing nonmetricity scalar Q0. However, the damping rate of gravitational waves is higher for electromagnetic perturbation. Time domain profiles for both types of perturbations were also investigated to confirm the quasinormal mode behavior.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
Gaetano Lambiase, Reggie C. Pantig, Dhruba Jyoti Gogoi, Ali Ovgun
Summary: The study investigates the relationship between the deformation parameter beta of the generalized uncertainty principle (GUP) and the two free parameters (omega) over cap and gamma of the running Newtonian coupling constant of the Asymptotic Safe gravity (ASG) program. By analyzing the shadow and quasinormal modes of black holes, the results confirm the consistency of ASG and GUP, and provide new insights into the nature of black holes and their signatures. The implications of these findings for future studies in quantum gravity are also discussed.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
H. B. Benaoum, Genly Leon, A. Ovgun, H. Quevedo
Summary: This study investigates inflation driven by a nonlinear electromagnetic field based on an NLED lagrangian density. The study formulates an f-NLED cosmological model with a general function f (F) and explores two interesting examples of the function f (F). The study also analyzes the implications of NLED by studying inflationary parameters and compares the results with observational data.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Astronomy & Astrophysics
Yi Yang, Dong Liu, Ali Ovgun, Zheng-Wen Long, Zhaoyi Xu
Summary: Gravitational decoupling can add hair to black holes, and we investigated the quasinormal modes of hairy black holes caused by gravitational decoupling. We derived the equations of effective potential for three perturbations in a hairy black hole spacetime and studied their time evolution. By analyzing the influence of the hairs (alpha, l0, and Q) on quasinormal modes, we found that alpha and l0 decrease the oscillation frequency of gravitational-wave signal, while Q increases it. Additionally, we calculated the bounds of the greybody factor and high-energy absorption cross section, showing that primary hair generated by charges (alpha and l0) can increase the probability of gravitational radiation reaching spatial infinity, while the charge Q from extra sources has the opposite effect.
