Article
Astronomy & Astrophysics
Jan Ambjorn, Yuki Hiraga, Yoshiyasu Ito, Yuki Sato
Summary: By quantizing the two-dimensional projectable Horava-Lifshitz gravity with bi-local and spacelike wormhole interaction, we find that the resulting quantum Hamiltonian coincides with that obtained through summing over all genus in the string field theory, implying that the wormhole interaction can be interpreted as a splitting or joining interaction of one-dimensional strings.
Article
Astronomy & Astrophysics
Paul Martens, Hiroki Matsui, Shinji Mukohyama
Summary: In this paper, we introduce a well-tempered DeWitt wave function that vanishes at the classical big-bang singularity in Horava-Lifshitz (HL) cosmology. Through analytical and numerical methods, we demonstrate that in HL gravity, the DeWitt wave function for tensor perturbation is well-defined at the singularity and behaves well up to the finite size of the Universe.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Celia Escamilla-Rivera, Hernando Quevedo
Summary: Proposing an alternative cosmography using Horava-Lifshitz gravity as a model for quantum gravity, the study suggests that the Universe appears flat classically according to the ΛCDM model, but is actually curved from a quantum perspective. The findings indicate a non-flat scenario and a specific value for the Horava parameter that could be interpreted as a measure of a quantum effect.
CLASSICAL AND QUANTUM GRAVITY
(2021)
Article
Physics, Multidisciplinary
Behnam Pourhassan, Izzet Sakalli
Summary: This paper investigates the thermodynamics of the Horava-Lifshitz black hole at quantum scales, focusing on the non-perturbative quantum correction. The study reveals that the stability of different solutions, such as Kehagius-Sfetsos and Lu-Mei-Pop, is affected differently by the non-perturbative quantum correction. The Lu-Mei-Pop solution remains stable in the presence of the correction.
CHINESE JOURNAL OF PHYSICS
(2022)
Article
Astronomy & Astrophysics
Hiroki Matsui, Shinji Mukohyama, Atsushi Naruko
Summary: The study shows that in many gravitational theories, the DeWitt wave function does not have the desired form when tensor perturbations are taken into account, but Hofava-Lifshitz gravity provides a satisfactory solution, especially an exact analytic expression for the DeWitt wave function of the universe with scale-invariant perturbations can be found in the limit of z = 3 anisotropic scaling.
Article
Physics, Particles & Fields
Alvaro Restuccia, Francisco Tello-Ortiz
Summary: This study obtained and analyzed a spherically symmetric solution of the field equations of the Horava-Lifshitz gravity-gauge vector interaction theory, describing a charged throat. The solution exists when a restriction on the relation between mass and charge is met, reducing to the Reissner-Nordstrom one as the coupling constants approach relativistic values. By introducing the correct charts, the solution can be described across the entire manifold, including the throat connecting different spacetimes.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Nuclear
Haizhen Ren, Zefeng Wang, Juhua Chen, Yongjiu Wang
Summary: This paper investigates the thermodynamic phase transitions of the HL gravity in the AdS black hole. The HP and small-large black hole phase transitions are found to occur under different conditions, and a relationship between them is proposed.
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
(2023)
Article
Astronomy & Astrophysics
Hugo Garcia-Compean, Daniel Mata-Pacheco
Summary: This study investigates the vacuum transition probabilities for a Friedmann-Lemaitre-Robertson-Walker universe with positive curvature in Horava-Lifshitz gravity, considering the presence of a scalar field potential. The Hamiltonian approach to the Wheeler-DeWitt equation is used to compute the transition probabilities. The study provides analytic expressions for the transition probabilities in two scenarios and discusses the infrared and ultraviolet limits in comparison to general relativity. Phenomenological implications, including a potential resolution of the initial singularity, are briefly discussed.
Article
Astronomy & Astrophysics
Mohammad Bagher Jahani Poshteh, Robert B. Mann
Summary: The thermodynamics of z = 4 Ho.rava-Lifshitz black holes in 3 + 1 dimensions is studied in extended phase space. By using the scaling argument, the Smarr relation and the first law for the black hole solutions of z = 4 Ho.rava-Lifshitz gravity are found. It is discovered that the reverse isoperimetric inequality can be violated for certain types of horizons, leading to positive specific heat at constant pressure and volume. Two critical points are identified for z = 4 Hovara-Lifshitz black holes with hyperbolic horizons, exhibiting both Van der Waals and reverse Van der Waals behaviors.
Article
Astronomy & Astrophysics
Alvaro Restuccia, Francisco Tello-Ortiz
Summary: An anisotropic model describing gravity-vector gauge coupling is proposed, based on the 4+1 dimensional non-projectable Ho.rava-Lifshitz gravity theory with a geometrical restriction. Renormalizability arguments require including interactions up to terms with z = 4 spatial derivatives on the geometrical tensor fields. The reduction to 3+1 dimensions results in a model invariant under FDiff and U(1) symmetry groups, propagating the same spectrum as the Einstein-Maxwell theory at the kinetic conformal point.
CLASSICAL AND QUANTUM GRAVITY
(2023)
Article
Astronomy & Astrophysics
Naritaka Oshita, Niayesh Afshordi, Shinji Mukohyama
Summary: This study investigates the ringdown waveform and reflectivity of a Lifshitz scalar field around a fixed Schwarzschild black hole, finding that Lifshitz waves scattered by the black hole exhibit superradiance due to Lorentz breaking terms leading to superluminal propagation. This can allow Lifshitz waves to carry additional positive energy to infinity while leaving negative energy inside the Killing horizon, similar to the Penrose process in Kerr spacetime. The study also observes the emergence of long-lived quasinormal modes and drastic modifications to the greybody factor of a microscopic black hole with Hawking temperature comparable to the Lifshitz energy scale.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
S. Jalalzadeh
Summary: We investigated the quantum deformation of the Wheeler-DeWitt equation for a Schwarzchild black hole and discovered the quantization, degeneracy, and boundedness of the event horizon area and mass. The degeneracy of states indicates the presence of entangled quantum black hole/white hole states, providing a new framework to study Einstein-Rosen wormhole solutions.
Article
Astronomy & Astrophysics
G. S. Vicente
Summary: This study considers classical and quantum Friedmann-Lemaitre-Robertson-Walker universes filled with noninteracting radiation and dust fluids within the framework of Horava-Lifshitz gravity theory. Analytical solutions for nonsingular quantum bounce and cyclic universes for open and closed spatial sections in terms of the parameters of Horava-Lifshitz theory were found. The Horava-Lifshitz theory was applied in its projectable version without the detailed balance condition, and canonical quantization was performed in the Wheeler-DeWitt approach of quantum cosmology for a minisuperspace model.
Article
Physics, Multidisciplinary
Mark Ho-Yeuk Cheung, Vishal Baibhav, Emanuele Berti, Vitor Cardoso, Gregorio Carullo, Roberto Cotesta, Walter Del Pozzo, Francisco Duque, Thomas Helfer, Estuti Shukla, Kaze W. K. Wong
Summary: We present evidence of nonlinear modes in the ringdown phase of gravitational waveforms generated by the merger of comparable-mass black holes. This evidence is based on numerical simulations of both quasicircular binary black hole coalescence and high-energy head-on collisions of black holes. The presence of nonlinear modes in the simulations highlights the importance of considering general-relativistic nonlinearities in the analysis of gravitational wave data.
PHYSICAL REVIEW LETTERS
(2023)
Article
Astronomy & Astrophysics
Guillermo Lara, Mario Herrero-Valea, Enrico Barausse, Sergey M. Sibiryakov
Summary: Horava gravity proposes completing general relativity by interactions violating Lorentz invariance at high energies, with solutions showing various geometric properties and uncertainty regarding their formation from gravitational collapse.
Article
Physics, Multidisciplinary
Salman Sajad Wani, James Q. Quach, Mir Faizal, Sebastian Bahamonde, Behnam Pourhassan
Summary: This study proposes that the Hamiltonian constraint in quantum gravity cannot probe change and therefore cannot provide a meaningful notion of time. It suggests that if the time-reparametrization symmetry is spontaneously broken, time can emerge in quantum gravity.
FOUNDATIONS OF PHYSICS
(2022)
Article
Physics, Nuclear
Behnam Pourhassan, Ujjal Debnath
Summary: In this paper, the theory of infinitely extended particles is considered as the quantum theory of gravity, which unifies all fundamental interactions. The space-time metric, similar to a Schwarzschild black hole, is written. The Hamiltonian and Lagrangian are calculated to obtain the potential energy and study polymer quantization. The effective potential and gravitational wave of this theory are discussed. The geodesic motion of a particle near the black hole is studied, and the apparent shape, radius, and distortion of the black hole shadow are analyzed.
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
(2022)
Article
Astronomy & Astrophysics
Jafar Sadeghi, Mehdi Shokri, Saeed Noori Gashti, Behnam Pourhassan, Prabir Rudra
Summary: This paper investigates the traversable wormhole solutions for a logarithmic corrected f(R) model by calculating the parameters of the model and studying different energy conditions.
INTERNATIONAL JOURNAL OF MODERN PHYSICS D
(2022)
Article
Astronomy & Astrophysics
Behnam Pourhassan, Anha Bhat, Hrishikesh Patel, Mir Faizal, Nicholas Mantella
Summary: This paper proposes an experimental test to verify the short distance modification of general relativity by Randall-Sundrum models. By analyzing the motion of a particle in a spherical gravitational field with drag force, the difference in the particle's stopping position in general relativity and Randall-Sundrum model can be measured. This measurement can be done using a nanoelectromechanical setup.
INTERNATIONAL JOURNAL OF MODERN PHYSICS D
(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
Physics, Nuclear
Mir Hameeda, Behnam Pourhassan, Syed Masood, Mir Faizal, Li-Gang Wang, Shohaib Abass
Summary: In this paper, the effects of expansion on large-scale structure formation in the universe are analyzed. By incorporating a cosmological constant term in the gravitational partition function, the thermodynamics and equation of state of the system are studied. The system's gravitational phase transition and distribution function are also analyzed, and the results are compared with observational data.
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
(2022)
Article
Physics, Particles & Fields
Behnam Pourhassan, Houcine Aounallah, Mir Faizal, Sudhaker Upadhyay, Saheb Soroushfar, Yermek O. Aitenov, Salman Sajad Wani
Summary: This article investigates the properties of the M2-M5 brane system as a black M2-M5 bound state, with a focus on the behavior of the system at short distances and the effects of quantum gravitational corrections. The quantum work for this solution is obtained using the Jarzynski equality, and the corrections to the thermodynamic stability of the system from quantum gravitational corrections are studied. The concept of a novel quantum mass is used to analyze the quantum gravitational corrections to the information geometry of the system.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Nuclear
M. Hameeda, Q. Gani, B. Pourhassan, M. C. Rocca
Summary: This study explores the nonfundamental force of gravity and uses Boltzmann and Tsallis statistical methods to study the thermodynamic properties in the braneworld model.
INTERNATIONAL JOURNAL OF MODERN PHYSICS A
(2022)
Article
Physics, Particles & Fields
Behnam Pourhassan, Mahdi Atashi, Houcine Aounallah, Salman Sajad Wani, Mir Faizal, Barun Majumder
Summary: In this paper, we investigate the effects of non-perturbative quantum gravitational corrections on a quantum sized AdS black hole. It will be observed that these corrections modify the stability of the black hole. Using non-equilibrium quantum thermodynamics, we study the evaporation process of the black hole between two states and analyze the effects of non-perturbative quantum gravitational corrections on this process. We explicitly obtain the quantum work distribution for the evaporating black hole and observe modifications due to the non-perturbative quantum gravitational corrections.
Article
Physics, Multidisciplinary
J. Sadeghi, B. Pourhassan, S. Noori Gashti, S. Upadhyay, E. Naghd Mezerji
Summary: The paper aims to confirm new universal relations in black hole thermodynamics. Different black holes are selected to investigate these relations. First, the thermodynamic relations are obtained by adding a minor correction to the AdS part of the action. Then, the universal relations are confirmed through direct calculations. It is notable that new universal relations can be obtained for each property related to black holes using this method. Two different types of these universal relations are confirmed for various black holes. Additionally, the black holes surrounded by perfect fluid satisfy the weak gravity conjecture condition, and new universal relations are derived.
Article
Astronomy & Astrophysics
Jafar Sadeghi, Behnam Pourhassan, Saeed Noori Gashti, Elaheh Naghd Mezerji, Antonio Pasqua
Summary: In this study, the inflationary scenario in logarithmic f (R) gravity is examined, with a focus on the constant-roll rate of inflation. The cosmic evolution of the logarithmic f (R) gravity is investigated using constant-roll conditions, and numerical and graphical analyses are presented. The resulting potential satisfying the constant-roll conditions is obtained and tested against the refined swampland conjecture and the latest observable data.
Article
Multidisciplinary Sciences
Sara Kanzi, Izzet Sakalli, Behnam Pourhassan
Summary: This study investigates the superradiant stability of a rotating black hole derived from the nonlinear Maxwell theory of gravity, f (R). The stability and instability evaluation is based on the absence and presence of the magnetic field, respectively, with magnetic field constants c(4 ) being 0 and c4 = 60. The study also analyzes the greybody factors (GFs) and quasi-normal modes (QNMs) of the black hole, with a focus on the effects of the nonlinear Maxwell f (R) gravity theory parameters on the effective potential, GFs, and QNMs.
Article
Astronomy & Astrophysics
Ujjal Debnath, Behnam Pourhassan, Izzet Sakalli
Summary: In this paper, a new charged AdS black hole with modified cosmic Chaplygin gas (MCCG) is constructed and its thermodynamics, energy conditions, and the efficiency of a heat engine are studied. The results show that the black hole is stable under certain conditions and can work as a heat engine.
MODERN PHYSICS LETTERS A
(2022)
Article
Physics, Particles & Fields
Houcine Aounallah, Behnam Pourhassan, Seyed Hossein Hendi, Mir Faizal
Summary: This paper analyzes a five-dimensional Yang-Mills black hole solution in massive gravity's rainbow, investigates the flow of such a solution with scale, discusses the scale dependence of the thermodynamics for this black hole, studies the criticality in the extended phase space treating the cosmological constant as the thermodynamics pressure, and uses the partition function to obtain corrections to the thermodynamics of this system and examine their key role in the behavior of corrected solutions.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
J. Sadeghi, B. Pourhassan, S. Noori Gashti, S. Upadhyay
Summary: This paper investigates a series of exact solutions of static wormholes with smeared mass source geometry in modified f(R) gravity theories. By solving the wormhole field equations, the resulting solutions are computed and plotted to describe the violation or satisfaction of energy conditions.
MODERN PHYSICS LETTERS A
(2022)
Article
Physics, Particles & Fields
Bogdan Damski
Summary: In this paper, we discuss the dynamics of field configurations in the Proca theory of the real massive vector field, specifically focusing on a certain class of electric (magnetic) dipole-charged states. We construct these states to ensure that the long-distance structure of the mean electromagnetic field is initially set by the formula describing the electromagnetic field of the electric (magnetic) dipole. We analyze the evolution of this mean electromagnetic field over time and observe the phenomena of harmonic oscillations of the electric (magnetic) dipole moment far from the center of the initial field configuration, as well as the emergence of a spherical shock wave propagating at the speed of light near the center. Additionally, we discover a unique axisymmetric mean electric field configuration accompanying the mean magnetic field in magnetic dipole-charged states.
Article
Physics, Particles & Fields
Brett McInnes
Summary: The time-dependence of AdS black hole interior geometries poses challenges to holographic duality and the traversability of wormholes. Quantum circuit complexity of strongly coupled matter can address the first challenge. Data from a phenomenological model show an upper bound on the complexity growth rate, which becomes stricter with the addition of angular momentum. The slowing of black hole interior dynamics at high specific angular momentum also occurs.
Article
Physics, Particles & Fields
M. Beccaria, S. Giombi, A. A. Tseytlin
Summary: This article investigates the superconformal index Z of the 6d (2,0) theory on S5 x S1 and describes it using the quantum M2 brane theory in the large N limit. By studying M2 branes in a twisted product of thermal AdS7 and S4, the leading non-perturbative term at large N is shown to be reproduced by the 1-loop partition function of an instanton M2 brane wrapped on S1 x S2 with S2 c S4. Similarly, the partition function of a defect M2 brane wrapped on thermal AdS3 c AdS7 reproduces the BPS Wilson loop expectation value in the (2,0) theory. The article also comments on the analogy of these results with similar computations in the quantum M2 brane partition function in AdS4 x S7/DOUBLE-STRUCK CAPITAL Zk, which reproduced the corresponding localization expressions in the ABJM 3d gauge theory.
Article
Physics, Particles & Fields
Carlos Silva
Summary: This paper explores the nature of spacetime in quantum gravity based on a new version of the holographic principle that establishes a connection between string theory and polymer holonomy structures. The research findings suggest that, for this relationship to hold, spacetime must be perceived as emerging from a fundamental structure with degrees of freedom corresponding to quantum correlations only.
Article
Physics, Particles & Fields
A. Senol, H. Denizli, C. Helveci
Summary: This study investigates new physics using a Monte Carlo method, and the results show stronger limitations on anomalous quartic gauge couplings compared to previous experiments.
