Article
Astronomy & Astrophysics
Gopal Yadav, Nitin Joshi
Summary: In this study, the researchers analyzed the information paradox and its resolution in Schwarzschild de-Sitter black hole spacetime using the island proposal. They found that the black hole island is located inside the black hole event horizon, contrary to the universal result for eternal black holes, and the cosmological island is also located inside the cosmological event horizon. Moreover, they studied the effect of temperature on Page curves and observed that low-temperature black hole/de-Sitter patch exhibits Page curves at later times, while high-temperature black hole/de-Sitter patch shows the opposite behavior.
Article
Astronomy & Astrophysics
Shin'ichi Nojiri, Sergei D. Odintsov, Tanmoy Paul
Summary: In this study, the Bekenstein-Hawking entropy is modified and a new entropy function is developed to derive the usual FLRW equations for matter fluids with different equation of state parameters. The research finds that by using a general entropy based on the Bekenstein-Hawking entropy, the Friedmann equations of the apparent horizon cosmology can be modified, leading to interesting cosmological consequences.
Article
Physics, Fluids & Plasmas
Ugur Cetiner, Jeremy Gunawardena
Summary: In this study, the properties of steady-state probabilities are investigated. It is found that steady-state probabilities are related to the entropy along minimal paths and can be expressed as averages over a probability distribution on spanning trees. By applying Arrhenius rates to the arboreal distribution, a thermodynamic interpretation for steady-state probabilities is provided. This approach extends equilibrium statistical mechanics and reorganizes the complexity of the expression.
Article
Astronomy & Astrophysics
Sourav Bhattacharya, Nitin Joshi
Summary: Investigated the degradation of quantum entanglement in the Schwarzschild-de Sitter black hole spacetime, finding that entanglement or correlation degrades with increasing Hawking temperatures, but does not degrade and even increases when considering both horizons combined.
Article
Astronomy & Astrophysics
Luis M. Sanchez, Hernando Quevedo
Summary: In this study, we investigate the relationship between gravity and thermodynamics in dynamic systems by considering the apparent horizon of the FLRW spacetime as a thermodynamic system. We derive the fundamental equation in the entropy representation and explore the consequences of satisfying classical laws of thermodynamics. Our investigation focuses on FLRW spacetimes with and without a cosmological constant. We find that the interpretation of the apparent horizon as an isolated thermodynamic system is only possible under certain conditions, as the analogy does not hold for all parameter values and the entire evolution of the horizon. However, we demonstrate that the generalized second law of thermodynamics remains valid.
Article
Physics, Particles & Fields
Bhramar Chatterjee, Narayan Banerjee
Summary: In this study, we examine radiation from cosmological apparent horizon in the FLRW model using a double-null coordinate setting. Due to the dynamic nature of spacetime, a Kodama vector is used as the dynamical time instead of a timelike Killing vector. By constructing the positive frequency modes of the Kodama vector across the horizon, we determine the temperature associated with the horizon based on the conditional probability of a signal reaching the central observer during crossing.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Astronomy & Astrophysics
Eirini Sourtzinou, Charis Anastopoulos
Summary: This paper investigates the thermodynamics of a small body near a black hole horizon using a first-principles analysis. The study focuses on a quantum ideal gas confined in a small box above the Schwarzschild horizon. The authors analyze the system in terms of free quantum fields and identify thermodynamic properties through the microcanonical distribution. They find that the effective dimension of the system changes as it approaches the horizon, and that the pressure is highly anisotropic. Additionally, they show that the approximation of quantum fields on a fixed background breaks down at microscopic distances from the horizon, requiring the inclusion of backreaction effects.
Article
Engineering, Chemical
Elijah Thimsen
Summary: This work elucidates methods based on nonequilibrium thermodynamics to predict the stationary states of chemical reactions in nonequilibrium plasma and the limits for energy conversion efficiency, using CO2 splitting as an example reaction. It was found that the probability of observing reactants or products increases with the energy dissipated by that side of the reaction as heat through collisions with hot electrons.
Article
Astronomy & Astrophysics
Prabir Rudra, Behnam Pourhassan
Summary: This study investigates the thermodynamic properties of the universe in the background of the generalized energy-momentum-squared gravity. By deriving the energy density of matter and performing thermodynamic analysis on two different models using the cosmic apparent horizon, it is found that stability analysis significantly constrains the parameter space of the models.
PHYSICS OF THE DARK UNIVERSE
(2021)
Article
Physics, Multidisciplinary
Qiwei Yu, Dongliang Zhang, Yuhai Tu
Summary: This study reveals that the energy dissipation rate in a nonequilibrium reaction system has an inverse power-law dependence on the number of microscopic states in a coarse-grained state, and requires self-similarity of the underlying network. The scaling exponent of the dissipation law depends on the network structure and the probability flux correlation. The existence of the inverse dissipation scaling law is demonstrated in realistic biochemical systems such as biochemical oscillators and microtubule-kinesin active flow systems.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Ahmad Sheykhi, Maral Sahebi Hamedan
Summary: The thermodynamics-gravity conjecture suggests a strong connection between the gravitational field equations and the first law of thermodynamics, meaning any changes in entropy expression directly impact the field equations. By considering the modified Barrow entropy associated with the apparent horizon, the Friedmann equations are altered as well. This paper explores the implications of this modification on the holographic dark energy (HDE) model, highlighting changes in energy density and the Friedmann equations. The study also investigates the cosmological consequences of using the Hubble horizon and future event horizon as infrared cutoffs, including interactions between dark matter (DM) and dark energy (DE), and the impact of the Barrow exponent on the cosmological behavior of HDE, such as crossing the phantom line and shifting the universe phase transition time.
Article
Chemistry, Physical
Faezeh Khodabandehlou, Christian Maes, Karel Netocny
Summary: We discuss when and why the steady nonequilibrium heat capacity vanishes with temperature using general arguments and examples. The framework of Markov jump processes on finite connected graphs is used, where the condition of local detailed balance helps identify the heat fluxes, and the discreteness enables a nondegenerate stationary distribution at absolute zero. Additionally, a dynamic condition is needed for the nonequilibrium extension of the Third Law to ensure that the low-temperature dynamical activity and accessibility of the dominant state remain sufficiently high.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Particles & Fields
G. Abbas, R. H. Ali
Summary: In this paper, we investigate the stability of large black holes under thermal fluctuations and explore the effects of these fluctuations on thermodynamic quantities and phase transition stability. We also examine null geodesics and photon sphere radius for a charged AdS BH and calculate the Lyapunov exponent and angular velocity. Additionally, we test the behavior of corrected thermodynamic quantities by observing the effects of correction and coupling parameters. Finally, we determine the stability of the system (under the influence of dark matter) by analyzing the specific heat and Hawking temperature, both of which are related to entropy.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Multidisciplinary
M. Z. Bhatti, Z. Yousaf, A. Rehman
Summary: In this manuscript, the validity of the horizon first law in the context of f(R,G)$f(R, \mathcal{G})$ gravity is evaluated. It is proposed that the energy and entropy of a black hole must be consistent with their respective integration values. The positivity of energy and entropy is shown to impose additional restrictions on the domain of f(R,G)$f(R, \mathcal{G})$ gravity.
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2023)
Article
Energy & Fuels
Michael H. Peters
Summary: The paper discusses the application of nonequilibrium statistical mechanics or molecular theory in transport equations of mass, momentum, energy, and entropy, and the closure of these equations leading to phenomenological laws. It also demonstrates how the complete set of transport equations can be simplified under physically restrictive assumptions and transformed into a new set of nonequilibrium thermodynamic functions.
Article
Physics, Nuclear
Sen Yang, Cheng Liu, Tao Zhu, Li Zhao, Qiang Wu, Ke Yang, Mubasher Jamil
Summary: This study investigates the spherical accretion flow onto general parametrized spherically symmetric black hole spacetimes, analyzing the accretion process for various perfect fluids. The influences of additional parameters beyond the Schwarzschild black hole on flow behavior are studied in detail, as well as the accretion of the ideal photon gas and its correspondence with the photon sphere for general parameterized spherically symmetric black holes. Possible extensions of the analysis are also discussed.
Article
Physics, Particles & Fields
Javlon Rayimbaev, Ahmadjon Abdujabbarov, Mubasher Jamil, Wen-Biao Han
Summary: This study investigates the effects of Einstein-(Ether gravity on magnetized particles orbiting a black hole immersed in a magnetic field, exploring the impact of free parameters on particle trajectories, innermost stable circular orbits, and collision energy. The study also compares these effects with those of rotating Kerr black holes, finding similar behavior for certain values. Additionally, the cases where a static /Ether black hole can be described as a Schwarzschild black hole in modified gravity are analyzed with corresponding parameter values.
Article
Astronomy & Astrophysics
Sourabh Nampalliwar, Saurabh Kumar, Kimet Jusufi, Qiang Wu, Mubasher Jamil, Paolo Salucci
Summary: This paper investigates the impact of a dark matter spike on the vicinity of the black hole Sgr A* in the center of the Milky Way. The study examines the influence of dark matter density on the shadow radius and image of the black hole, concluding that the effect is weak for realistic densities but may become significant at higher densities near the black hole. However, simulations with radio interferometry, similar to an EHT array, suggest that detecting this effect in the near future is unlikely.
ASTROPHYSICAL JOURNAL
(2021)
Article
Physics, Particles & Fields
Javlon Rayimbaev, Sanjar Shaymatov, Mubasher Jamil
Summary: This paper investigates circular orbits around a black hole surrounded by dark matter, showing how dark matter impacts the existence of circular orbits and exploring its applications in fitting and explaining black hole parameters.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Correction
Physics, Particles & Fields
Sanjar Shaymatov, Bobomurat Ahmedov, Mubasher Jamil
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Mathematical
Kimet Jusufi, Mustapha Azreg-Ainou, Mubasher Jamil, Tao Zhu
Summary: This paper investigates the effects of the Generalized Uncertainty Principle (GUP) on the shadow and quasinormal modes (QNMs) of GUP-modified Kerr black holes. The study reveals that the GUP modification increases the curvature radius of the shadow and that it increases linearly with the GUP parameter. By using observational data and fitting techniques, the upper limits of the GUP parameter and the correction parameter in the modified black hole metric are determined.
INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
(2022)
Article
Astronomy & Astrophysics
Kimet Jusufi, Mustapha Azreg-Ainou, Mubasher Jamil, Emmanuel N. Saridakis
Summary: Using observations of the central black hole and stars, we extract constraints on Barrow entropy, finding an upper bound less strong than the Big Bang Nucleosynthesis but significantly stronger than late-time cosmological constraints.
Article
Astronomy & Astrophysics
Javlon Rayimbaev, Bushra Majeed, Mubasher Jamil, Kimet Jusufi, Anzhong Wang
Summary: In this article, we investigate the particle dynamics around a Bardeen-Kiselev black hole, including its geometrical properties, the dynamics of test particles, and the relationship with rotating Kerr black hole.
PHYSICS OF THE DARK UNIVERSE
(2022)
Article
Astronomy & Astrophysics
Kimet Jusufi, Mustapha Azreg-Ainou, Mubasher Jamil, Qiang Wu
Summary: This paper focuses on the relationship between quasinormal modes (QNMs) and a rotating black hole shadow, using the example of a quantum deformed Kerr black hole. The study shows that, in the eikonal limit, the real part of QNMs is related to the Keplerian frequency for equatorial orbits. The paper also explores the typical shadow radius, computes the corresponding modes, and investigates the thermodynamical stability of the quantum deformed Kerr black hole, as well as other astrophysical applications.
Article
Astronomy & Astrophysics
Javlon Rayimbaev, Ahmadjon Abdujabbarov, Mubasher Jamil, Wen-Biao Han, Malika Khudoyberdieva
Summary: This paper discusses the motion of various types of charged, magnetized, and neutral test particles near static and spherically symmetric electrically charged black holes in the Einstein-/Ether gravitational theory. The effects of the free parameters in the theory on particle motion in curved spacetime are analyzed, focusing on the stability of circular and radially varying orbits for different types of particles. The behavior of charged particle motion around black holes with a uniform magnetic field is investigated, and values of the parameters c13 and c14 are proposed to model astrophysical black holes based on the spin of Kerr black holes.
MODERN PHYSICS LETTERS A
(2022)
Article
Physics, Nuclear
Farruh Atamurotov, Mubasher Jamil, Kimet Jusufi
Summary: In this study, the optical properties of a renormalization group improved Schwarzschild black hole in a plasma medium are investigated. The deflection angle of light in the weak gravity regime is computed for uniform and non-uniform plasma media, revealing the modifications caused by the plasma medium. The effects of plasma media play an important role in the optical appearance of black holes.
Article
Physics, Particles & Fields
Kimet Jusufi, Salvatore Capozziello, Sebastian Bahamonde, Mubasher Jamil
Summary: We use observational data to constrain a black hole solution of extended teleparallel gravity models based on the S2 star orbiting the Galactic Center. We construct the shadow images of the Sgr A* black hole and find that the shadow radius increases with the parameter alpha. The observables, such as the deflection angle and angular diameter, are close to the Schwarzschild case. However, the electromagnetic intensity observed in the shadow images is smaller compared to General Relativity (GR), indicating differences in the Born-Infeld f(T) gravity.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
Kimet Jusufi, Saurabh Kumar, Mustapha Azreg-Ainou, Mubasher Jamil, Qiang Wu, Cosimo Bambi
Summary: In this study, we investigate the possibility of a wormhole as a candidate for the central object of Sgr A(star) and test this idea by constraining their geometry using the motion of S2 star and the reconstructed shadow images. We consider three wormhole models and find that they satisfy the flare out condition. We also explore the accretion of infalling gas model and study the accretion rate, electromagnetic radiation intensity, and shadow images.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
Sanjar Shaymatov, Mubasher Jamil, Kimet Jusufi, Kazuharu Bamba
Summary: In this study, we investigate the dynamics of test particles around a magnetized Ernst black hole, taking into account its surrounding magnetic field. We find that the magnetic field has a significant impact on the radius of the innermost stable circular orbit (ISCO) and the epicyclic frequencies, especially for charged particles. By analyzing the astrophysical quasiperiodic oscillation (QPO) data of three microquasars, we determine the order of magnitude of the magnetic field.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
Farruh Atamurotov, Kimet Jusufi, Mubasher Jamil, Ahmadjon Abdujabbarov, Mustapha Azreg-Ainou
Summary: This paper investigates the influence of axion-plasmon on the optical properties of Schwarzschild black hole. It is found that the size of the black hole shadow decreases with increasing axion-plasmon coupling, indicating changes in gravitational deflection angle and other properties.