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In this study, we explore gravitational lensing using more realistic dark matter halo models, moving beyond the limitations of spherical-collapse approximations. Through analytical calculations employing various mass functions, we address…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-13 Ali Tizfahm , Saeed Fakhry , Javad T. Firouzjaee , Antonino Del Popolo

We give the lens equation for light deflections caused by point mass condensations in an otherwise spatially homogeneous and flat universe. We assume the signal from a distant source is deflected by a single condensation before it reaches…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Bin Chen , Ronald Kantowski , Xinyu Dai

We propose a new numerical technique for following the evolution of a self-gravitating collisionless system in general relativity. Matter is modeled as a scalar field obeying the coupled Klein-Gordon and Einstein equations. A phase space…

Astrophysics · Physics 2009-10-28 Lawrence M. Widrow

This paper studies the deflection of charged particles in a dipole magnetic field in Schwarzschild spacetime background in the weak field approximation. To calculate the deflection angle, we use Jacobi metric and Gauss-Bonnet theorem. Since…

General Relativity and Quantum Cosmology · Physics 2022-12-28 Zonghai Li , Wei Wang , Junji Jia

The image of a point situated at the center of a circularly symmetric potential is a perfect circle. The perturbative effect of non-symmetrical potential terms is to displace and break the perfect circle. These 2 effects, displacement and…

Astrophysics · Physics 2009-11-13 C. Alard

We investigate how observations of strong lensing can be used to infer cosmological parameters, in particular the equation of state of dark energy. We focus on the growth of the critical lines of lensing clusters with the source redshift as…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-03 Britta Zieser , Matthias Bartelmann

We study the effects of gravitational lensing on neutrino oscillations in the $\gamma$-spacetime which describes a static, axially-symmetric and asymptotically flat solution of the Einstein's field equations in vacuum. Using the…

General Relativity and Quantum Cosmology · Physics 2022-01-26 Hrishikesh Chakrabarty , Debasish Borah , Ahmadjon Abdujabbarov , Daniele Malafarina , Bobomurat Ahmedov

In this manuscript, we study the nearly flat approximation of a conformally invariant gravitational theory in metric measure space (MMS). In addition, we investigate the transformation of the energy-momentum tensor in this context and…

General Relativity and Quantum Cosmology · Physics 2023-02-28 Samaneh Oghbaiee , Nafiseh Rahmanpour , Hossein Shojaie

Finding strong gravitational lenses in astronomical images allows us to assess cosmological theories and understand the large-scale structure of the universe. Previous works on lens detection do not quantify uncertainties in lens parameter…

Instrumentation and Methods for Astrophysics · Physics 2022-11-22 Yash Patel , Jeffrey Regier

We propose the back reaction to the charged galactic wormhole spacetime based on Yoshiaki Sofue's exponential dark matter density profile to find exact solutions. The charges act as an additional component to the static wormhole, which is…

General Physics · Physics 2025-12-19 Md Khalid Hossain , Farook Rahaman

If it is hypothesised that there is no dark matter then some alternative gravitational theory must take the place of general relativity (GR) on the largest scales. Dynamical measurements can be used to investigate the nature of such a…

Astrophysics · Physics 2008-11-26 Daniel J. Mortlock , Edwin L. Turner

Astrophysical observations provide compelling evidence for the existence of dark matter, a non-luminous component dominating the universe's mass-energy budget. Its gravitational influence is well-established on galactic scales; however,…

General Relativity and Quantum Cosmology · Physics 2025-06-06 Jan Kuncewicz

In this paper the problem of gravitational deflection of relativistic charged massive particles in slowly rotating Kerr-Newman black holes is considered. Toward this purpose we have used two methods: Firstly, we have applied the…

General Relativity and Quantum Cosmology · Physics 2019-07-01 Kimet Jusufi

Strong lensing has developed into an important astrophysical tool for probing both cosmology and galaxies (their structure, formation, and evolution). Using the gravitational lensing theory and cluster mass distribution model, we try to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Shuo Cao , Yu Pan , Marek Biesiada , Wlodzimierz Godlowski , Zong-Hong Zhu

It is a common assumption amongst astronomers that, in the determination of the distances of remote sources from their apparent brightness, the cumulative gravitational lensing due to the matter in all the galaxies is the same, on average,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Clarissa-Marie Claudel

We present a numerical technique to compute the gravitational lensing induced by simulated haloes. It relies on a 2D-Tree domain decomposition in the lens plane combined with a description of N-Body particles as extended clouds with a…

Astrophysics · Physics 2008-11-26 Dominique Aubert , Adam Amara , R. Benton Metcalf

The gravitational lensing of supermassive black holes surrounded by dark matter halo has attracted a great number of interests in recent years. However, many studies employed simplified dark matter density models, which makes it very hard…

General Relativity and Quantum Cosmology · Physics 2024-10-25 Yi-Gao Liu , Chen-Kai Qiao , Jun Tao

Density fluctuations in the matter distribution lead to distortions of the images of distant galaxies through weak gravitational lensing effects. This provides an efficient probe of the cosmological parameters and of the density field. In…

Astrophysics · Physics 2007-05-23 P. Valageas

Using the gradient expansion approach, we formulate a nonlinear cosmological perturbation theory on super-horizon scales valid to $O(\epsilon^2)$, where $\epsilon$ is the expansion parameter associated with a spatial derivative. For…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yoshiharu Tanaka , Misao Sasaki

Gravitational lensing of gravitational waves provides a powerful probe of the mass density distribution in the universe. Wave optics effects, such as diffraction, make the lensing effect sensitive to the structure around the Fresnel scale,…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-22 So Tanaka , Teruaki Suyama
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