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Related papers: General Theorem about Gravitational Lensing

200 papers

The last decade has shown a considerable development of gravitational lensing for cosmology because it probes the amount and the nature of dark matter, and provides information on the density parameter $\Omega$, the cosmological constant…

Astrophysics · Physics 2007-05-23 Y. Mellier , F. Bernardeau , L. van Waerbeke

The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent Standard Solar Model (SSM) data. The Sun's minimum focal length is computed to a refined accuracy of 23.5 +/- 0.1 AU, just…

Astrophysics · Physics 2011-12-13 Bijunath Patla , Robert J. Nemiroff

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

The recent classical nonlocal generalization of Einstein's theory of gravitation is presented within the framework of general relativity via the introduction of a preferred frame field. The nonlocal generalization of Einstein's field…

General Relativity and Quantum Cosmology · Physics 2015-06-22 B. Mashhoon

An explanation is proposed for the fact that pp-waves superpose linearly when they propagate parallely, while they interact nonlinearly, scatter and form singularities or Cauchy horizons if they are antiparallel. Parallel pp-waves do…

General Relativity and Quantum Cosmology · Physics 2015-06-25 V. Faraoni , R. M. Dumse

For a general class of analytic f(R)-gravity theories, we discuss the weak field limit in view of gravitational lensing. Though an additional Yukawa term in the gravitational potential modifies dynamics with respect to the standard…

General Relativity and Quantum Cosmology · Physics 2012-02-09 M. Lubini , C. Tortora , J. Näf , Ph. Jetzer , S. Capozziello

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 gravitational lensing effect is one of the most promising tools for cosmology. Indeed it probes directly the total mass distribution in large-scale structures and can as well provide valuable informations on the values of the density…

Astrophysics · Physics 2007-05-23 Y. Mellier , L. van Waerbeke , F. Bernardeau , B. Fort

Generalized symmetrons are models that have qualitatively similar features to the archetypal symmetron, but have barely been studied. In this article, we investigate for what parameter values the fifth forces induced by disformally coupling…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-12 Christian Käding

We present the first detailed computations of wave optics effects in the gravitational lensing of binary systems. The field is conceptually rich, combining the caustic singularities produced in classical gravitational lensing with quantum…

General Relativity and Quantum Cosmology · Physics 2020-08-06 Job Feldbrugge , Neil Turok

Gravitational lensing - the deflection of light rays by gravitating matter - has become a major tool in the armoury of the modern cosmologist. Proposed nearly a hundred years ago as a key feature of Einstein's theory of General Relativity,…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Tommaso Treu , Richard S. Ellis

Gravitational lensing represents a powerful tool to estimate the cosmological pa- rameters and the distribution of dark matter. I will describe the main observable quantities, concentrating on strong lensing, that manifests its effect…

Astrophysics · Physics 2007-05-23 C. Tortora

It has been recently shown that the lens equation for a binary gravitational lens, which is apparently a coupled system, can be reduced to a real fifth-order (quintic) algebraic equation. Some algebraic properties of the real quintic…

Astrophysics · Physics 2009-11-07 Hideki Asada , Taketoshi Kasai , Masumi Kasai

Frequency-dependent gravitational lens effects are found for trajectories of electromagnetic rays passing through a distribution of plasma near a massive object. Ray propagation through plasma adds extra terms to the equations of motion…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Adam Rogers

Galaxies acting as gravitational lenses are surrounded by, at most, a handful of images. This apparent paucity of information forces one to make the best possible use of what information is available to invert the lens system. In this…

Astrophysics · Physics 2009-11-13 J. Liesenborgs , S. De Rijcke , H. Dejonghe , P. Bekaert

Using Fermat's principle, we analyze the effects of very long wavelength gravitational waves upon the images of a gravitationally lensed quasar. We show that the lens equation in the presence of gravity waves is equivalent to that of a lens…

Astrophysics · Physics 2011-09-09 J. Frieman , D. Harari , G. Surpi

This article deals with the gravitational lensing (GL) of gravitational waves (GW). We compute the increase in the number of detected GW events due to GL. First, we check that geometrical optics is valid for the GW frequency range on which…

General Relativity and Quantum Cosmology · Physics 2009-11-10 M. Arnaud-Varvella , M. -C. Angonin , Ph. Tourrenc

For gravitational deflections of massless particles of given helicity from a classical rotating body, we describe the general relativity corrections to the geometric optics approximation. We compute the corresponding scattering cross…

General Relativity and Quantum Cosmology · Physics 2010-11-19 A. Barbieri , E. Guadagnini

In the present manuscript, I examine an intriguing relation at the classical level between general relativity and a theory where matter couples uniquely multiplicatively to geometry in the Lagrangian density. Interestingly, the…

General Relativity and Quantum Cosmology · Physics 2018-12-20 Olivier Minazzoli

For suitable gravitational lens systems with unknown lens redshifts, the redshifts and brightnesses (in different colours) of the lenses are predicted for a variety of cosmological models, for both elliptical and spiral galaxy lenses.…

Astrophysics · Physics 2007-05-23 Phillip Helbig