260 citations · 6.2k across the 131 of their papers we have counts for
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Deflection of light by black holes and massless wormholes in massive gravity
Kimet Jusufi, Nayan Sarkar, Farook Rahaman +2
Weak gravitational lensing by black holes and wormholes in the context of massive gravity (Bebronne and Tinyakov 2009) theory is studied. The particular solution examined is charac…
Effect of the cosmological constant on the deflection angle by a rotating cosmic string
Kimet Jusufi, Ali Övgün
We report the effect of the cosmological constant and the internal energy density of a cosmic string on the deflection angle of light in the spacetime of a rotating cosmic string w…
Hawking Radiation in the Spacetime of White Holes
Kimet Jusufi
A white hole (WH) is a time-reversed black hole (BH) solution in General relativity with a spacetime region to which cannot be entered from the outside. Recently they have been pro…
Falsifying cosmological models based on a non-linear electrodynamics
Ali Övgün, Genly Leon, Juan Magaña +1
Recently, the nonlinear electrodynamics (NED) has been gaining attention to generate primordial magnetic fields in the Universe and also to resolve singularity problems. Moreover,…
Quantum Tunneling and Quasinormal Modes in the Spacetime of Alcubierre Warp Drive
Kimet Jusufi, İzzet Sakallı, Ali Övgün
In a seminal paper, Alcubierre showed that Einstein's theory of general relativity appears to allow a super-luminal motion. In the present study, we use a recent eternal-warp-drive…
Semiclassical gravitational effects on the gravitational lensing in the spacetime of topological defects
Kimet Jusufi, Farook Rahaman, Ayan Banerjee
The theory of gravitational lensing has revealed many generic and fundamental properties of compact objects like black holes and wormholes. In this article, we utilize a recent for…
Gravitational Lensing by Rotating Wormholes
Kimet Jusufi, Ali Övgün
In this paper the deflection angle of light by a rotating Teo wormhole spacetime is calculated in the weak limit approximation. We mainly focus on the weak deflection angle by reve…
Stable Gravastars: Guilfoyle's electrically charged solutions
Ayan Banerjee, J. R. Villanueva, Phongpichit Channuie +1
Compelling alternatives to black holes, namely, gravitational vacuum star ({\it gravastar}) models, the multilayered structure compact objects, have been proposed to avoid a number…
Light Deflection by a Quantum Improved Kerr Black Hole Pierced by a Cosmic String
Kimet Jusufi, Ali Övgün
In this work, we calculate the quantum correction effects on the deflection of light in the spacetime geometry of a quantum improved Kerr black hole pierced by an infinitely long c…
Light deflection by charged wormholes in Einstein-Maxwell-dilaton theory
Kimet Jusufi, Ali Övgün, Ayan Banerjee
In this paper, we study the deflection of light by a class of charged wormholes within the context of the Einstein-Maxwell-dilaton theory. The primordial wormholes are predicted to…
Effect of Lorentz Symmetry Breaking on the Deflection of Light in a Cosmic String Spacetime
Kimet Jusufi, İzzet Sakallı, Ali Övgün
We investigate the Lorentz symmetry breaking effects (LSBE) on the deflection of light by a rotating cosmic string spacetime in the weak limit approximation. We first calculate the…
Stability of Effective Thin-shell Wormholes Under Lorentz Symmetry Breaking Supported by Dark Matter and Dark Energy
Ali Övgün, Kimet Jusufi
In this paper, we construct generic, spherically symmetric thin-shell wormholes and check their stabilities using the unified dark sector, including dark energy and dark matter. We…
Deflection Angle of Light by Wormholes using the Gauss-Bonnet Theorem
Kimet Jusufi
In this letter, we have investigated the deflection angle of light by wormholes using a new geometrical method known as Gibbons-Werner method (GW). In particular we have calculated…
Charged Thin-shell Gravastars in Noncommutative Geometry
Ali Övgün, Ayan Banerjee, Kimet Jusufi
In this paper we construct a charged thin-shell gravastar model within the context of noncommutative geometry. To do so, we choose the interior of the nonsingular de Sitter spaceti…
The Effect of GUP to Massive Vector and Scalar Particles Tunneling From a Warped DGP Gravity Black Hole
Ali Övgün, Kimet Jusufi
This paper discusses the effects of the mass and the angular momentum of massive vector and scalar particles on the Hawking temperature manifested under the effects of the generali…
Tunneling of Massive/Massless Bosons From the Apparent Horizon of FRW Universe
Kimet Jusufi, Ali Ovgun, Gordana Apostolovska
In this article we investigate the Hawking radiation of vector particles from the apparent horizon of a Friedmann-Robertson-Walker (FRW) universe in the framework of quantum tunnel…
Geodesics and Quantum Singularities in (1+1)-dimensional Horava-Lifshitz Gravity
Ali Övgün, Kimet Jusufi
This paper has been withdrawn by the author due to a crucial sign error in equation which we use from Ref. 7 that is incorrect. In particular, Eq.(1-8) is not the correct equation…
Light Deflection by a Rotating Global Monopole Spacetime
Kimet Jusufi, Marcus C. Werner, Ayan Banerjee +1
We investigate the deflection of light by a rotating global monopole spacetime and a rotating Letelier spacetime in the weak deflection approximation. To this end, we apply the Gau…