520 citations · 1.8k across the 29 of their papers we have counts for
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Generating Spherically Symmetric Static Anisotropic Fluid Solutions of Einstein's Equations from Hydrostatic Equilibrium
M M Akbar, R Solanki
For static fluid spheres, the condition of hydrostatic equilibrium is given by the generalized Tolman--Oppenheimer--Volkoff (TOV) equation, a Riccati equation in the radial pressur…
Algorithms for Generating All Static Spherically Symmetric (An)isotropic Fluid Solutions of Einstein's Equations
M M Akbar, R Solanki
We study the Einstein equations of the static spherically symmetric anisotropic fluid system in curvature coordinates to find algorithms that generate all solutions and all solutio…
Embedding FLRW Geometries in Pseudo-Euclidean and Anti-de Sitter Spaces
M. M. Akbar
Contrary to the general consensus in the literature that Friedmann--Lemaître--Robertson--Walker (FLRW) geometries are of embedding class one (i.e.,\ embeddable in one higher dimens…
Spherical Spacelike Geometries in Static Spherically Symmetric Spacetimes: Generalized Painlevè-Gullstrand Coordinates, Foliation, and Embedding
M. M. Akbar
It is well known that static spherically symmetric spacetimes can admit foliations by flat spacelike hypersurfaces, which are best described in terms of the Painlevè--Gullstrand co…
Static Axisymmetric Einstein Equations in Vacuum: Symmetry, New Solutions and Ricci Solitons
M. M. Akbar, M. A. H. MacCallum
An explicit one-parameter Lie point symmetry of the four-dimensional vacuum Einstein equations with two commuting hypersurface-orthogonal Killing vector fields is presented. The pa…
Pseudo-Riemannian Ricci-flat and Flat Warped Geometries and New Coordinates for the Minkowski metric
M. M. Akbar
It is well-known that the Einstein condition on warpedgeometries requires the fibres to be necessarily Einstein. However, exact warped solutions have often been obtained using one-…
Thermodynamic Geometry Of Charged Rotating BTZ Black Holes
M. Akbar, H. Quevedo, K. Saifullah +2
We study the thermodynamics and the thermodynamic geometries of charged rotating BTZ (CR-BTZ) black holes in (2+1)-gravity. We investigate the thermodynamics of these systems withi…
Dynamics and Thermodynamics of (2+1)-Dimensional Evolving Lorentzian Wormhole
M. Umar Farooq, M. Akbar, Mubasher Jamil
In this paper we study the relationship between the Einstein field equations for the (2+1)-dimensional evolving wormhole and the first law of thermodynamics. It has been shown that…
Charged Rotating BTZ Black Hole and Thermodynamic Behavior of Field Equations at its Horizon
M. Akbar, Azad A. Siddiqui
In this paper, we study different cases of the charged rotating BTZ black hole with reference to their horizons. For the existence of these cases conditions on mass, charge and ang…
Generalized second law of thermodynamics for a phantom energy accreting BTZ black hole
Mubasher Jamil, M. Akbar
In this paper, we have studied the accretion of phantom energy on a (2+1)-dimensional stationary Banados-Teitelboim-Zanelli (BTZ) black hole. It has already been shown by Babichev…
Quantum corrections to the entropy of Einstein-Maxwell dilaton-axion black holes
M. Akbar, K. Saifullah
We study the corrections to the entropy of Einstein-Maxwell dilaton-axion black holes beyond semiclassical approximations. We consider the entropy of the black hole as a state vari…
Quantum corrections to the entropy of charged rotating black holes
M. Akbar, K. Saifullah
Hawking radiation from a black hole can be viewed as quantum tunneling of particles through the event horizon. Using this approach we provide a general framework for studying corre…
Generalized Second Law of Thermodynamics in Extended Theories of Gravity
M. Akbar
By employing the general expression of temperature associated with the apparent horizon of…
Ricci Solitons and Einstein-Scalar Field Theory
M M Akbar, E Woolgar
B List has recently studied a geometric flow whose fixed points correspond to static Ricci flat spacetimes. It is now known that this flow is in fact Ricci flow modulo pullback by…
Viscous Cosmology and Thermodynamics of Apparent Horizon
M. Akbar
It is shown that the differential form of Friedmann equations of FRW universe can be recast as a similar form of the first law, , of thermodynamics at the a…
Thermodynamic Behavior of Field Equations for f(R) Gravity
M. Akbar, Rong-Gen Cai
Recently it has shown that Einstein's field equations can be rewritten into a form of the first law of thermodynamics both at event horizon of static spherically symmetric black ho…
symmetries of the Ricci tensor of static space times with maximal symmetric transverse spaces
M. Akbar
Static space times with maximal symmetric transverse spaces are classified according to their Ricci collineations. These are investigated for non-degenerate Ricci tensor ($det.(R_α…
Classical Boundary-value Problem in Riemannian Quantum Gravity and Taub-Bolt-anti-de Sitter Geometries
M. M. Akbar
For an -invariant boundary the classical Dirichlet problem of Riemannian quantum gravity is studied for positive-definite regular solutions of the Einstein…
Classical Boundary-value Problem in Riemannian Quantum Gravity and Self-dual Taub-NUT-(anti)de Sitter Geometries
M. M. Akbar, P. D. D'Eath
The classical boundary-value problem of the Einstein field equations is studied with an arbitrary cosmological constant, in the case of a compact () boundary given a biaxial…