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Related papers: Gravitational Lensing by Cosmic String Loops

200 papers

Understanding of the signatures of cosmic string networks is limited by a large uncertainty in the sizes at which cosmic string loops form. We review cosmic string network evolution, and the gravitational signatures, with emphasis on this…

Astrophysics · Physics 2007-11-07 Joseph Polchinski

We report the detection of anomalous brightness fluctuations in the multiple image Q0957+561 A,B gravitational lens system, and consider whether such anomalies have a plausible interpretation within the framework of cosmic string theory. We…

Astrophysics · Physics 2009-11-10 R. Schild , I Masnyak , B. Hnatyk , V. Zhdanov

In this work we introduced a new proposal to study the gravitational lensing theory by spherical lenses, starting from its surface mass density $\Sigma(x)$ written in terms of a decreasing function $f$ of a dimensionless coordinate $x$ on…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-21 Roger Hurtado , Leonardo Castaneda , Juan M. Tejeiro

We present a framework that reformulates gravitational lensing as an optical phenomenon governed by an effective refractive index, enabling exploration of modified gravity theories using undergraduate-level mathematics and optics. After…

General Relativity and Quantum Cosmology · Physics 2026-04-09 Romy Hanang Setya Budhi

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 revealing the gravitational lensing as a partially global…

General Relativity and Quantum Cosmology · Physics 2018-01-31 Kimet Jusufi , Ali Övgün

Vector perturbations sourced by topological defects can generate rotations in the lensing of background galaxies. This is a potential smoking gun for the existence of defects since rotation generates a curl-like component in the weak…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Daniel B. Thomas , Carlo R. Contaldi , Joao Magueijo

Cosmic superstring loops within the galaxy microlens background point sources lying close to the observer-string line of sight. For suitable alignments, multiple paths coexist and the (achromatic) flux enhancement is a factor of two. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Jolyon K. Bloomfield , David F. Chernoff

Gravitational lensing allows us to probe the structure of matter on a broad range of astronomical scales, and as light from a distant source traverses an intervening galaxy, compact matter such as planets, stars, and black holes act as…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-09 Hugh Garsden , Geraint F. Lewis

Gravitational lensing by a spiral galaxy occurs when the line-of-sight to a background quasar passes within a few kpc from the center of the galactic disk. Since galactic disks are rich in neutral hydrogen, the quasar spectrum will likely…

Astrophysics · Physics 2016-08-30 Abraham Loeb

The wave effect in the gravitational lensing phenomenon by a straight cosmic string is investigated. The interference pattern is expressed in terms of a simple formula. We demonstrate that modulations of the interfered wave amplitude can be…

Astrophysics · Physics 2009-11-10 Kazuhiro Yamamoto , Keiji Tsunoda

Gravitational lensing is the deflection of light rays due to the gravity of intervening masses. This phenomenon is observed in a variety of scales and configurations, involving any non-uniform mass such as planets, stars, galaxies, clusters…

It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily…

Astrophysics · Physics 2008-11-26 M. Sereno

The long-standing problem of whether the cosmological constant affects directly the deflection of light caused by a gravitational lens is reconsidered. We use a new approach based on the Hawking quasilocal mass of a sphere grazed by light…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Valerio Faraoni , Marianne Lapierre-Leonard

Gravitational lensing is the phenomenon arising when light rays are deflected by the mass between the source and the observer. Largely magnified and highly distorted images of background galaxies are formed by these angular deflections if…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Atınç Çağan Şengül

The possibility to detect cosmic strings -- topological defects of early Universe, by means of wave effects in gravitational lensing is discussed. To find the optimal observation conditions, we define the hyperbolic-shaped Fresnel…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-05 Isabel Fernández-Núñez , Oleg Bulashenko

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 formulation to compute the quantum effects on the deflection…

General Relativity and Quantum Cosmology · Physics 2018-01-11 Kimet Jusufi , Farook Rahaman , Ayan Banerjee

Gravitational lensing directly measures mass density fluctuations along the lines of sight to very distant objects. No assumptions need to be made concerning bias, the ratio of fluctuations in galaxy density to mass density. Hence, lensing…

Astrophysics · Physics 2007-05-23 Joachim Wambsganss , Renyue Cen , Jeremiah P. Ostriker

Cosmic strings are important remnants of early-Universe phase transitions. We show that they can be probed by Gravitational Waves (GWs) from compact binary mergers. If such chirping GW passes by a cosmic string, it is gravitationally lensed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-05 Sunghoon Jung , TaeHun Kim

We analyzed the influence of static gravitational field on the vacuum and proposed the concept of inhomogeneous vacuum. According to the corresponding Fermat's principle in the general relativity, we derived a graded refractive index of…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Xing-Hao Ye , Qiang Lin

Gravitational lensing in clusters of galaxies is an efficient tool to probe the mass distribution of galaxies and clusters, high redshift objects thanks to the gravitational amplification, and the geometry of the universe. We review some…

Astrophysics · Physics 2009-10-31 M. Hattori , J. -P. Kneib , N. Makino