314 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Ain Shams UniversityEG110 papers
- University of SouthamptonGB108 papers
- Rutherford Appleton LaboratoryGB80 papers
- Texas A&M UniversityUS76 papers
- Université Libre de BruxellesBE74 papers
- Florida Institute of TechnologyUS73 papers
- Panjab UniversityIN73 papers
- University of DelhiIN73 papers
- University of SeoulKR73 papers
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di FrascatiIT72 papers
- Lappeenranta-Lahti University of TechnologyFI72 papers
- Universidad de AntioquiaCO72 papers
16 papers · 1 filter
More on Bianchi I spacetimes and f(T) gravity
Alexey Golovnev, Mustafa M. Hemida
Bianchi I cosmological solutions in f(T) gravity are discussed. We start from diagonal metrics and tetrads and show that their dynamical equations are pretty much tractable analyti…
Primordial Gravitational Waves in Generalized Palatini Gravity
Durmuş Demir, Khalid Gabriel, Ammar Kasem +1
Extended Palatini gravity is the metric-affine gravity theory characterized by zero torsion, nonzero metricity and a quadratic of the antisymmetric Ricci curvature. It reduces dyna…
The Implications of N = 2 Supergravity Cosmology On the Topology of the Calabi-Yau Manifold
Safinaz Salem, Moataz H. Emam, H. H. Salah
When N= D=11 supergravity is compactified on CY threefold to N=2 D=5 supergravity the action of the last is given in terms of the geometery of the CY manifold space, namely, in ter…
Rainbow Spacetime from a Nonlocal Gravitational Uncertainty Principle
Omar El-Refy, Syed Masood, Li-Gang Wang +1
Occurrence of spacetime singularities is one of the peculiar features of Einstein gravity, signalling limitation on probing short distances in spacetime. This alludes to the existe…
Degenerate Bogdanov-Takens bifurcations in a bulk viscous cosmology
Asmaa Abdel Azim, Adel Awad, E. I. Lashin
Using the dynamical system theory we show that the Friedmann-Robertson-Walker (FRW) cosmological model with bulk viscous fluid in the presence of cosmological constant is equivalen…
Comment on "Quantum Raychaudhuri equation"
E. I. Lashin, Djamel Dou
We address the validity of the formalism and results presented in [ S. Das, Phys. Rev. {\bf D89} 084068 (2014)] with regard to quantum Raychaudhuri equation. The author obtained th…
On the correctness of cosmology from quantum potential
E. I. Lashin
We examine in detail the cosmology based on quantal (Bohmian) trajectories as suggested in a recent study arXiv:1404.3093[gr-qc]. We disagree with the conclusions regarding predict…
Discreteness of time in the evolution of the universe
Mir Faizal, Ahmed Farag Ali, Saurya Das
In this paper, we will first derive the Wheeler-DeWitt equation for the generalized geometry which occurs in M-theory. Then we will observe that M2-branes act as probes for this ge…
A Proposal for Testing Gravity's Rainbow
Ahmed Farag Ali, Mohammed M. Khalil
Various approaches to quantum gravity such as string theory, loop quantum gravity and Horava-Lifshitz gravity predict modifications of the energy-momentum dispersion relation. Magu…
Absence of an Effective Horizon for Black Holes in Gravity's Rainbow
Ahmed Farag Ali, Mir Faizal, Barun Majumder
We argue that the divergence in time for the asymptotic observer occurs because of specifying the position of the Horizon beyond the Planck scale. In fact, a similar divergence in…
Minimal Length, Friedmann Equations and Maximum Density
Adel Awad, Ahmed Farag Ali
Inspired by Jacobson's thermodynamic approach[gr-qc/9504004], Cai et al [hep-th/0501055,hep-th/0609128] have shown the emergence of Friedmann equations from the first law of thermo…
Cosmology from quantum potential
Ahmed Farag Ali, Saurya Das
It was shown recently that replacing classical geodesics with quantal (Bohmian) trajectories gives rise to a quantum corrected Raychaudhuri equation (QRE). In this article we deriv…
Planck-Scale Corrections to Friedmann Equation
Adel Awad, Ahmed Farag Ali
Recently, Verlinde proposed that gravity is an emergent phenomenon which originates from an entropic force. In this work, we extend Verlinde's proposal to accommodate generalized u…
Towards a Cosmology with Minimal Length and Maximal Energy
Ahmed Farag Ali, Barun Majumder
The Friedmann-Robertson-Walker (FRW) universe and Bianchi I,II universes are investigated in the framework of the generalized uncertainty principle (GUP) with a linear and a quadra…
Nonsingular Rainbow Universes
Adel Awad, Ahmed Farag Ali, Barun Majumder
In this work, we study FRW cosmologies in the context of gravity rainbow. We discuss the general conditions for having a nonsingular FRW cosmology in gravity rainbow. We propose th…
Fixed points and FLRW cosmologies: Flat case
Adel Awad
We use phase space method to study possible consequences of fixed points in flat FLRW models. One of these consequences is that a fluid with a finite sound speed, or a differentiab…