Article
Physics, Particles & Fields
Bei Sha, Zhi-E Liu
Summary: In this study, the tunneling radiation characteristics of fermions and bosons in Vaidya-Bonner de Sitter black hole space-time were corrected by considering Lorentz symmetry breaking theory. The new modified forms of Dirac equation for fermions with spin 1/2 and Klein-Gordon equation for bosons in the curved space-time of the black hole were obtained. Through solving these equations, new and corrected expressions for surface gravity, Hawking temperature, and tunneling rate of the black hole were obtained and discussed.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Multidisciplinary
Sunandan Gangopadhyay, Siham Sen, Rituparna Mandal
Summary: In this work, we calculate the Hawking temperature for a quantum corrected black hole geometry using the reflection from the horizon method. We observe that quantum gravity corrections indeed show up in the Hawking temperature formula of the quantum corrected black hole. It is important to notice that the quantum gravity corrections arise in the Hawking temperature formula only due to the underlying quantum gravity corrections to the lapse function of the black hole metric rather than the semi-classical methods used in the analysis. We also substantiate our result by computing the Hawking temperature using the tunneling approach.
Article
Physics, Multidisciplinary
Sam Patrick, Harry Goodhew, Cisco Gooding, Silke Weinfurtner
Summary: Research has shown that fluid mechanical analogue black hole systems exhibit significant global mass changes in the presence of waves, leading to the possibility of studying backreaction with the presence of a dynamical metric.
PHYSICAL REVIEW LETTERS
(2021)
Article
Astronomy & Astrophysics
Pratik Ghosal, Rajarshi Ray
Summary: The nonthermal correction to the emission probability of particles from black holes is significant as it helps determine the probability of complete black hole evaporation and matches the initial entropy of the black hole. The study reveals that this probability distribution resembles Wien's displacement law for blackbody radiation.
Article
Physics, Multidisciplinary
Ahmad Al-Badawi, Sara Kanzi, Izzet Sakalli
Summary: This study focuses on the spinorial wave equations and greybody radiation in the NUT black hole spacetime. By using the Newman-Penrose formalism, the Dirac equation in NUT spacetime is analyzed, separating it into radial and angular components to discuss associated solutions and potentials. Additionally, the Klein-Gordon equation is studied to compute greybody factors, with a detailed investigation into the impact of the NUT parameter on the spacetime's greybody factors.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Astronomy & Astrophysics
Ren Tsuda, Shinya Tomizawa, Ryotaku Suzuki
Summary: We propose a new simple model of an acoustic black hole in a thin tube by utilizing the difference in gravitational potential to generate transonic flow. The analytical solution for the Euler equations can be obtained in our transonic flow model, providing an exact solution in terms of a height function for the monatomic case with gamma 1/4 5/3. By the near-sonic approximation, we find a simple form for arbitrary gamma. Additionally, two analytic solutions describing a backward wave and a forward wave are obtained, demonstrating the existence of sonic horizons.
Article
Materials Science, Multidisciplinary
Riasat Ali, Rimsha Babar, Zunaira Akhtar, Ali Ovgun
Summary: In this paper, the researchers investigate the effect of quantum gravity on the symmergent black hole derived from quadratic-curvature gravity. A modified Klein-Gordon equation, incorporating the generalized uncertainty principle (GUP), is used to study the tunneling and Hawking temperature of the symmergent black hole. The stability conditions of the black hole under the influence of GUP are examined by analyzing the temperature graphs near the outer horizon. The impact of thermal fluctuations on the thermodynamics of the black hole spacetime is also analyzed, including the evaluation of logarithmic correction terms for entropy and the viability of the first law of thermodynamics.
RESULTS IN PHYSICS
(2023)
Article
Astronomy & Astrophysics
Sofia Di Gennaro, Yen Chin Ong
Summary: This study investigates the evolution of charged black holes and the emission process under Hawking evaporation. Previous studies have suggested that extremal black holes may be effectively singular, violating the cosmic censorship conjecture. The study uses a simplified model and finds that having only a finite species of charged particles can actually lead to some end states becoming naked singularities.
Article
Physics, Multidisciplinary
Yang Wei
Summary: This study focuses on the Hawking radiation of the SL(n,R) Toda black hole and its related information loss problem. By calculating the tunneling effect of zero rest mass particles near the event horizon, the Hawking radiation of the four-dimensional static spherical symmetric SL(n,R) Toda black hole is investigated. The results support the tunneling model proposed by Parikh and Wilczek, indicating a deviation from a pure thermal spectrum and the existence of correlations between non-thermal spectra. Additionally, the study reveals that information conservation remains true when gravitational correlations among Hawking radiations are properly taken into account.
ACTA PHYSICA SINICA
(2023)
Article
Physics, Particles & Fields
Sareh Eslamzadeh, Javad T. Firouzjaee, Kourosh Nozari
Summary: In this paper, we investigate the 4D Einstein-Gauss-Bonnet black hole and its thermodynamics. The study includes the analysis of three different asymptotic spacetimes and the correlation between emission modes and temperature. The results show interesting behaviors of temperature and emission in different spacetime backgrounds.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Multidisciplinary
Xia Tan, Jie Zhang, Ran Li
Summary: This paper studies the modified forms of dynamic equations for bosons and fermions in curved space-time, taking into account the Lorentz breaking theory. By introducing an aether-like vector field and constructing gamma matrix correctly, new meaningful expressions for the dynamic equation of spin 1/2 Dirac particles in black hole space-time in gravity's rainbow are obtained, as well as the corresponding expressions for Hawking temperature, tunneling rate, and Bekenstein-Hawking entropy of the black hole. In addition, the distribution characteristics of Dirac particle energy levels are also studied, yielding meaningful results.
Article
Physics, Particles & Fields
Jie Zhang, Menquan Liu, Zhie Liu, Shuzheng Yang
Summary: The Kinnersley spacetime describes a non-spherical symmetric, non-stationary, and accelerating black hole, and can be used to study the collision characteristics of two black holes. By considering the Lorentz dispersion relation, we obtained a modified radiation temperature at the event horizon and the colliding temperature at the touch point of Rindler horizon and the event horizon.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
Behnam Pourhassan
Summary: This paper investigates the Hawking tunneling radiation of the charged rotating black hole in five-dimensional minimal supergravity theory using the semiclassical Hamilton-Jacobi equation. The corrected entropy of the black hole is obtained through two separated methods, and the equality of the results suggests a special condition to potentially solve the information loss paradox. The study also explores phase transitions, revealing that the black hole is unstable when the effects of thermal fluctuations are taken into account in the entropy, and phase transitions occur based on the sign-changing behavior of the black hole specific heat. Additionally, it is found that the black holes in five-dimensional minimal supergravity exhibit similar behavior to black holes in Horava-Lifshitz gravity in the presence of thermal fluctuations, indicating the possibility of a second-order phase transition.
Article
Astronomy & Astrophysics
Yasusada Nambu, Sousuke Noda
Summary: This study investigates the optical imaging of black holes with Hawking radiation. It calculates the spatial correlation function of Hawking radiation and obtains the optical images of black holes through Fourier transformation. The study finds that interference can enhance the brightness of images near the photon sphere.
Article
Physics, Multidisciplinary
Zhi-E Liu, Xia Tan, Jie Zhang, Shu-Zheng Yang
Summary: The quantum tunneling radiation of spin 1/2 fermions in Kerr anti-de-Sitter black holes was studied, with corrections made to the dynamic equation using Lorentz's violation theory. New expressions were obtained for the fermions quantum tunneling rate, black hole's Hawking temperature, and black hole's entropy. It was found that the Hawking temperature increases with the enhancement of coupling strength and radial component of ether-like field, independent of non-radial components.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2021)
Article
Physics, Nuclear
Farruh Atamurotov, Ibrar Hussain, Ghulam Mustafa, Ali Ovgun
Summary: In this study, the gravitational deflection angle of photons in the weak field limit and shadow cast by the electrically charged and spherically symmetric static Kiselev black hole in the string cloud background are investigated. The influences of the BH charge Q, quintessence parameter gamma, and string cloud parameter a on the weak deflection angle, radius of photon spheres, and size of the BH shadow are studied. Moreover, the effects of plasma on the weak deflection angle and shadow cast by the charged-Kiselev BH surrounded by the clouds of strings are analyzed. Data from the Event Horizon Telescope collaboration are used to obtain constraints on the values of the parameters gamma and a.
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
Multidisciplinary Sciences
Wajiha Javed, Mehak Atique, Reggie C. Pantig, Ali Ovgun
Summary: In this study, we investigated the weak lensing effects of a Reissner-Nordstrom black hole corrected by a bounce parameter in plasma and dark matter mediums. Using optical geometry and the Gibbons-Werner approach, we found that these mediums increase the bending angle of the black hole. Additionally, we examined the impact of the bounce parameter on the deflection angle of light and computed the Hawking radiation using a topological method.
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
Astronomy & Astrophysics
Akhil Uniyal, Reggie C. Pantig, Ali Ovgun
Summary: This paper investigates the asymptotically flat black hole solution in Einstein-nonlinear electrodynamics (NLE) fields and explores the effects of NLE parameters on the black hole deflection angle. The study employs the Gauss-Bonnet theorem for weak field limits, shadow casting using null geodesics, and thin accretion disk modeling. The research also examines various physical quantities such as energy flux, disk temperature, differential luminosity, emission profiles, and spherical accretion, and provides constraints on the NLE parameters based on observations of M87* and Sgr A* from EHT.
PHYSICS OF THE DARK UNIVERSE
(2023)
Article
Materials Science, Multidisciplinary
Riasat Ali, Rimsha Babar, Zunaira Akhtar, Ali Ovgun
Summary: In this paper, the researchers investigate the effect of quantum gravity on the symmergent black hole derived from quadratic-curvature gravity. A modified Klein-Gordon equation, incorporating the generalized uncertainty principle (GUP), is used to study the tunneling and Hawking temperature of the symmergent black hole. The stability conditions of the black hole under the influence of GUP are examined by analyzing the temperature graphs near the outer horizon. The impact of thermal fluctuations on the thermodynamics of the black hole spacetime is also analyzed, including the evaluation of logarithmic correction terms for entropy and the viability of the first law of thermodynamics.
RESULTS IN PHYSICS
(2023)
Article
Astronomy & Astrophysics
Ghulam Abbas, Ali Ovgun, Asif Mahmood, Muhammad Zubair
Summary: In this paper, strong deflection gravitational lensing in a conformal gravity black hole is studied. By using geometric optics limits, we have derived the light cone conditions for photons coupled to the Weyl tensor in a conformal gravity black hole. It is found that strong deflection gravitational lensing depends explicitly on the coupling with the Weyl tensor, the polarization directions, and the black hole configuration parameters. The results of strong deflection gravitational lensing have been applied to the supermassive black holes SgrA* and M87* to study the possibility of encountering quantum improvement. However, it is unlikely to recognize similar black holes through the observable effects of strong deflection gravitational lensing in the near future, except for the possible size of the black hole's shadow. It is also noted that applying the constraint of the measured shadow of M87* directly requires great caution due to quantum effects.
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
Dhruba Jyoti Gogoi, Ali Ovgun, Durmus Demir
Summary: This paper examines the black holes in symmergent gravity and investigates the effects of relevant parameters on their quasinormal modes and greybody factors. The findings suggest that the absolute values of the parameter cO play a crucial role in the quasinormal mode spectrum, and the symmergent parameter alpha strongly influences both the quasinormal mode spectrum and the greybody factors.
PHYSICS OF THE DARK UNIVERSE
(2023)
Article
Physics, Multidisciplinary
Ali Ovgun, Lemuel John F. Sese, Reggie C. Pantig
Summary: This paper derives four spherically symmetric black hole solutions surrounded by spherical dark matter distribution under the influence of the generalized uncertainty principle. It explores the impact of the quantum correction parameter, gamma, on a toy model galaxy with different dark matter distributions. The study applies these solutions to known supermassive black holes and reveals unique deviations in event horizon and shadow radii, providing constraints on gamma.
ANNALEN DER PHYSIK
(2023)
Article
Physics, Particles & Fields
Yashmitha Kumaran, Ali Ovgun
Summary: This paper investigates a solution for an asymptotic, magnetically-charged, non-singular (AMCNS) black hole by utilizing Gauss-Bonnet theorems. It explores various aspects associated with this unique black hole, such as the gravitational field, light bending, shadow, and greybody bounding. Through rigorous calculations and simulations, the weak deflection angle of the optical metric of the AMCNS black hole is derived, and the impact of dark matter medium on the deflection angle is investigated, along with the distinctive features of the black hole's shadow and its greybody factors.
EUROPEAN PHYSICAL JOURNAL C
(2023)
