2.4k citations · 12k across the 222 of their papers we have counts for
24 papers · 1 filter
Thermodynamics in Rastall Gravity with Entropy Corrections
Kazuharu Bamba, Abdul Jawad, Salman Rafique +1
We explore the thermodynamic analysis at the apparent horizon in the framework of Rastall theory of gravity. We take different entropies such as the Bakenstein, logarithmic correct…
The arbitrariness of potentials in interacting quintessence models
Nandan Roy, Kazuharu Bamba
We study the interacting quintessence model with two different types of interaction by introducing a general parameterization of the quintessence potentials. The form of the quinte…
Axially magnetized Dark Energy cosmological model
B. Mishra, Pratik P Ray, S. K. Tripathy +1
We investigate the behaviour of the skewness parameters for an anisotropic universe in the framework of General Relativity. Non interacting dark energy is considered in presence of…
`Hidden' symmetry of linearized gravity in de Sitter space
Hamed Pejhan, Surena Rahbardehghan, Mohammad Enayati +2
We demonstrate that the linearized Einstein gravity in de Sitter (dS) spacetime besides the evident symmetries also possesses the additional (local) symmetry $h_{μν}\rightarrow h_{…
Traversable Wormholes with Exponential Shape Function in Modified Gravity and in General Relativity: A Comparative Study
Gauranga C. Samanta, Nisha Godani, Kazuharu Bamba
We have proposed a novel shape function on which the metric that models traversable wormholes is dependent. Using this shape function, the energy conditions, equation of state and…
Nonlinear electrodynamics, singularities and accelerated expansion
Gauranga C. Samanta, Shantanu K. Biswal, Kazuharu Bamba
Non-linear electrodynamics coupled to general relativity is investigated. In general relativity, it is observed that the expansion of the universe is accelerating if the source of…
A small non-vanishing cosmological constant from the Krein-Gupta-Bleuler vacuum
Hamed Pejhan, Kazuharu Bamba, Mohammad Enayati +1
We point out a potential relevance between the Krein-Gupta-Bleuler (KGB) vacuum leading to a fully covariant quantum field theory for gravity in de Sitter (dS) spacetime and the ob…
Hairy black holes and holographic heat engine
Hossein Ghaffarnejad, Emad Yaraie, Mohammad Farsam +1
By considering AdS charged black hole in the context of extended thermodynamic as the working substance we use it as a heat engine. We investigate the effect of hairy charge on the…
Reconstruction of lagrangian from a massive scalar field
Soumya Chakrabarti, Kazuharu Bamba, Jackson Levi Said
We present a reconstruction of the Lagrangian for gravity by using a massive scalar field. The scalar field is minimally coupled to the action of gravity. We demonstr…
Charged rotating black holes coupled with nonlinear electrodynamics Maxwell field in the mimetic gravity
G. G. L. Nashed, W. El Hanafy, Kazuharu Bamba
In mimetic gravity, we derive -dimension charged black hole solutions having flat or cylindrical horizons with zero curvature boundary. The asymptotic behaviours of these black…
New Exact Spherically Symmetric Solutions in gravity by Noether's symmetry approach
Sebastian Bahamonde, Kazuharu Bamba, Ugur Camci
The exact solutions of spherically symmetric space-times are explored by using Noether symmetries in gravity with the scalar curvature, a scalar field and th…
Dynamical Instability of Spherical Anisotropic Sources in Gravity
Z. Yousaf, Kazuharu Bamba, M. Z. Bhatti +1
In this paper, we study the effects of modification of gravity on the problem of dynamical instability of the spherical relativistic anisotropic interiors. We have considered non-z…
Bouncing cosmology in gravity
J. K. Singh, Kazuharu Bamba, Ritika Nagpal +1
A cosmological model with a specific form of the Hubble parameter is constructed in a flat homogeneous, and isotropic background in the framework of gravity, where is…
Holographic Entanglement Entropy, Complexity, Fidelity Susceptibility and Hierarchical UV/IR Mixing Problem in $AdS_2/\mbox{open strings}$
Kazuharu Bamba, Davood Momeni, Mudhahir Al Ajmi
In this paper, we will compute the holographic complexity (dual to a volume in AdS), holographic fidelity susceptibility and the holographic entanglement entropy (dual to an area i…
A Note on Tsallis Holographic Dark Energy
M. Abdollahi Zadeh, A. Sheykhi, H. Moradpour +1
We explore the effects of considering various infrared (IR) cutoffs, including the particle horizon, Ricci horizon and Granda-Oliveros (GO) cutoffs, on the properties of Tsallis ho…
Holographic dark energy through Tsallis entropy
Emmanuel N. Saridakis, Kazuharu Bamba, R. Myrzakulov +1
In order to apply holography and entropy relations to the whole universe, which is a gravitational and thus nonextensive system, for consistency one should use the generalized defi…
Spherically symmetric charged black hole in conformal teleparallel equivalent of general relativity
G. G. L. Nashed, Kazuharu Bamba
We study 4-dimensional non-charged and charged spherically symmetric spacetimes in conformal teleparallel equivalent of general relativity. We apply the gravitational field equatio…
Pendulum Leptogenesis
Kazuharu Bamba, Neil D. Barrie, Akio Sugamoto +2
We propose a new non-thermal Leptogenesis mechanism that takes place during the reheating epoch, and utilizes the Ratchet mechanism. The interplay between the oscillation of the in…
Dynamical properties of Bianchi-I spacetimes in gravity
Saikat Chakraborty, Kazuharu Bamba, Alberto Saa
We present a dynamical analysis in terms of new expansion-normalized variables for homogeneous and anisotropic Bianchi-I spacetimes in gravity in the presence of anisotropic…
Analysis with observational constraints in -cosmology in gravity
Ritika Nagpal, S. K. J. Pacif, J. K. Singh +2
An exact cosmological solution of Einstein field equations (EFEs) is derived for a dynamical vacuum energy in gravity for Friedmann-Lemaitre-Robertson-Walker (FLRW) space-…
Observational constraints on the jerk parameter with the data of the Hubble parameter
Abdulla Al Mamon, Kazuharu Bamba
We study the accelerated expansion phase of the universe by using the {\textit{kinematic approach}}. In particular, the deceleration parameter is parametrized in a model-indepe…
Tsallis Holographic Dark Energy
M. Tavayef, A. Sheykhi, Kazuharu Bamba +1
Employing the modified entropy-area relation suggested by Tsallis and Cirto \cite{non3}, and the holographic hypothesis, a new holographic dark energy (HDE) model is proposed. Cons…
On the propagation of gravitational waves in strong magnetic fields
Kazuharu Bamba, Shin'ichi Nojiri, Sergei D. Odintsov
The propagation of gravitational waves is explored in the cosmological context. It is explicitly demonstrated that the propagation of gravitational waves could be influenced by the…
"Massless" spin-2 field in de Sitter space
Hamed Pejhan, Kazuharu Bamba, Surena Rahbardehghan +1
In this paper, admitting a de Sitter (dS)-invariant vacuum in an indefinite inner product space, we present a Gupta-Bleuler type setting for causal and full dS-covariant quantizati…