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Related papers: Gravitational Lensing by Cosmic String Loops

200 papers

In this article, we develop a formalism which is different from the standard lensing scenario and is necessary for understanding lensing by gravitational fields which arise as solutions of the effective Einstein equations on the brane. We…

General Relativity and Quantum Cosmology · Physics 2008-12-30 Supratik Pal , Sayan Kar

It has been recently shown that Hoyle-Narlikar's C-field theory admits wormhole geometry. We derive the deflection angle of light rays caused by C-field wormhole in the strong field limit approach of gravitational lensing theory. The…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Rahaman , M. Kalam , S. Chakraborty

We investigate exact and approximate techniques to calculate the emission of gravitational radiation from cosmic string loops in order to generate beam models covering the entire celestial sphere for a wide range of modes $m$. One approach…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-27 Namitha Suresh , David F. Chernoff

In light of the surge in popularity of electromagnetic cloaking devices, we consider whether it is possible to use gravitational lensing to cloak a volume of spacetime. A metric for such a spacetime geometry is presented, and its geometric…

General Relativity and Quantum Cosmology · Physics 2012-10-30 Benjamin K. Tippett

The mean spectrum and burst statistics of gravitational waves produced by a cosmological population of cosmic string loops are estimated using analytic approximations, calibrated with earlier simulations. Formulas are derived showing the…

Astrophysics · Physics 2009-11-11 Craig J. Hogan

This review forms the Weak Lensing part of the Saas-Fee Advanced Course on Gravitational Lensing. It describes the basicsm applications and results of weak lensing. Contents: (1) Introduction (2) The principles of weak gravitational lensing…

Astrophysics · Physics 2009-11-11 Peter Schneider

The purpose of these lecture notes is to describe the gravitational lens effects in different astrophysical contexts. These notes are voluntarily focused on the fundamental mechanisms and the basic concepts that are useful to describe these…

Astrophysics · Physics 2007-05-23 F. Bernardeau

We study gravitational lensing by a class of zero Ricci scalar wormholes which arise as solutions in a scalar-tensor theory of gravity. An attempt is made to find a possible link between lensing features, stable/unstable photon orbits and…

General Relativity and Quantum Cosmology · Physics 2017-08-29 Rajibul Shaikh , Sayan Kar

We present a new formula for the rate at which cosmic strings lose energy into gravitational radiation, valid for all piecewise-linear cosmic string loops. At any time, such a loop is composed of $N$ straight segments, each of which has…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Bruce Allen , Paul Casper

Gravitational lensing time delays offer an avenue to measure the Hubble parameter $H_0$, with some analyses suggesting a tension with early-type probes of $H_0$. The lensing measurements must mitigate systematic uncertainties due to the…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Kfir Blum , Luca Teodori

Gravitational lensing affects observed cosmological correlation functions because observed images do not coincide with true source locations. We treat this universal effect in a general way here, deriving a single formula that can be used…

Astrophysics · Physics 2008-11-26 Scott Dodelson , Fabian Schmidt , Alberto Vallinotto

We study the deformation of a long cosmic string by a nearby rotating black hole. We examine whether the deformation of a cosmic string, induced by the gravitational field of a Kerr black hole, may lead to the formation of a loop of cosmic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Florian Dubath , Mairi Sakellariadou , Claude Michel Viallet

We consider the possible effects of gravitational lensing by globular clusters on gravitational waves from asymmetric neutron stars in our galaxy. In the lensing of gravitational waves, the long wavelength, compared with the usual case of…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Andrew J. Moylan , David E. McClelland , Susan M. Scott , Antony C. Searle , G. V. Bicknell

Some aspects of gravitational lensing by large scale structure (LSS) are investigated. We show that lensing causes the damping tail of the cosmic microwave background (CMB) power spectrum to fall less rapidly with decreasing angular scale…

Astrophysics · Physics 2015-06-24 R. Benton Metcalf , Joseph Silk

Weak lensing is the distortion (polarization) of images of distant objects, such as high redshift galaxies, by gravitational fields in the limit where the distortion is small. Gravitational potential fluctuations due to large scale…

Astrophysics · Physics 2015-06-24 Jens Verner Villumsen

Deflection of light by gravity was predicted by General Relativity and observationaly confirmed in 1919. In the following decades various aspects of the gravitational lens effect were explored theoretically, among them the possibility of…

Astrophysics · Physics 2015-06-24 Joachim Wambsganss

In this work we study gravitational lensing of the wormhole in the Eddington-inspired Born-Infeld (EiBI) spacetime that incorporates with a cosmic string. It was found that the presence of cosmic string can enhance the light deflection in…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Xin-Fei Li , Lei-Hua Liu , Yan-Zhi Meng , Shu-Qing Zhong , Li-Juan Zhou

We study analytically a gravitational lens due to a deformed star, which is modeled by using a monopole and a quadrupole moment. Positions of the images are discussed for a source on the principal axis. We present explicit expressions for…

Astrophysics · Physics 2009-11-10 Hideki Asada

LISA might detect gravitational waves from mergers of massive black hole binaries strongly lensed by intervening galaxies (Sereno et al. 2010). The detection of multiple gravitational lensing events would provide a new tool for cosmography.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Sereno , Ph. Jetzer , A. Sesana , M. Volonteri

When moduli roll in the early universe, all physical scales - including string tensions - simultaneously evolve. The dynamics of cosmic string loops with time-varying tension can produce cosmic string loop trackers in which most of the…

High Energy Physics - Phenomenology · Physics 2025-11-21 Joseph P. Conlon , Edmund J. Copeland , Edward Hardy , Noelia Sánchez González