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Related papers: Weak lensing and the Dyer-Roeder approximation

200 papers

The standard theory of weak gravitational lensing relies on the approximation that light beams are infinitesimal. Our recent work showed that the finite size of sources, and the associated light beams, can cause nonperturbative corrections…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-29 Pierre Fleury , Julien Larena , Jean-Philippe Uzan

The interpretation of cosmological observations relies on a notion of an average Universe, which is usually considered as the homogeneous and isotropic Friedmann-Lema\^itre-Robertson-Walker (FLRW) model. However, inhomogeneities may…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Michel-Andrès Breton , Pierre Fleury

The standard cosmological parallax--distance formula, as found in the literature, including text-books and reference books on cosmology, requires a correction. This correction stems from the fact that in the standard text-book derivation it…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-04 Ashok K. Singal

Weak gravitational lensing is responsible for the shearing and magnification of the images of high-redshift sources due to the presence of intervening matter. The distortions are due to fluctuations in the gravitational potential, and are…

Astrophysics · Physics 2009-09-29 D. Munshi , P. Valageas , L. Van Waerbeke , A. Heavens

We discuss how inhomogeneities of the universe affect observations of the gravitational lensing; (1) the bending angle, (2) the lensing statistics and (3) the time delay. In order to take account of the inhomogeneities, the Dyer-Roeder…

Astrophysics · Physics 2009-10-30 Hideki Asada

This paper and the others in the series challenge the standard model of the effects of gravitational lensing on observations at large distances. We show that due to the cumulative effect of lensing, areas corresponding to an observed solid…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Nazeem Mustapha , B. A. Bassett , Charles Hellaby , G. F. R. Ellis

Here we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 T. D. Kitching , A. F. Heavens , L. Miller

We present the correlation function of the luminosity distances in a flat $\Lambda$CDM universe. Decomposing the luminosity distance fluctuation into the velocity, the gravitational potential, and the lensing contributions, we study their…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Sang Gyu Biern , Jaiyul Yoo

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

Next generation gravitational waves (GWs) observatories are expected to measure GW signals with unprecedented sensitivity, opening new, independent avenues to learn about our Universe. The distance-redshift relation is a fulcrum for…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Sofia Canevarolo , Nora Elisa Chisari

We study the large-scale inhomogeneity of the Universe based on the averaging procedure of Buchert and Ehlers. The generalized Dyer-Roeder equation for the angular diameter distance of the inhomogeneous Universe is derived and solved for…

Astrophysics · Physics 2010-11-11 D. Palle

(Abridged) Weak gravitational lensing is an ideal probe of the dark universe. In recent years, several linear methods have been developed to reconstruct the density distribution in the Universe in three dimensions, making use of photometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Adrienne Leonard , François-Xavier Dupé , Jean-Luc Starck

We calculate the systematic inhomogeneity-induced correction to the cosmological constant that one would infer from an analysis of the luminosities and redshifts of Type Ia supernovae, assuming a homogeneous universe. The calculation…

Astrophysics · Physics 2008-12-18 R. Ali Vanderveld , Eanna E. Flanagan , Ira Wasserman

The standard treatment of gravitational lensing by a point mass lens M is based on a weak-field deflection angle a = 2/x, where x = (r c^2)/(2 G M) with r the distance of closest approach to the mass of a lensed light ray. It was shown that…

Astrophysics · Physics 2009-11-07 A. O. Petters

High redshift sources suffer from magnification or demagnification due to weak gravitational lensing by large scale structure. One consequence of this is that the distance-redshift relation, in wide use for cosmological tests, suffers…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Madhura Killedar , Paul D. Lasky , Geraint F. Lewis , Chris J. Fluke

Whilst the underlying assumption of the Friedman-Lema\^itre-Robertson-Walker (FLRW) cosmological model is that matter is homogeneously distributed throughout the universe, gravitational influences over the life of the universe have resulted…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Sonia Akter Ema , Md Rasel Hossen , Krzysztof Bolejko , Geraint F. Lewis

In view of interpreting the cosmological observations precisely, especially when they involve narrow light beams, it is crucial to understand how light propagates in our statistically homogeneous, clumpy, Universe. Among the various…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-26 Pierre Fleury

More than half of the volume of our Universe is occupied by cosmic voids. The lensing magnification effect from those under-dense regions is generally thought to give a small dimming contribution: objects on the far side of a void are…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Krzysztof Bolejko , Chris Clarkson , Roy Maartens , David Bacon , Nikolai Meures , Emma Beynon

In this work we investigate the weak lensing convergence using an end-to-end nonlinear general relativistic framework. Combining numerical relativity simulations of large-scale structure formation with general relativistic ray-tracing, we…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-27 Hayley J. Macpherson

We have obtained analytical exact solutions of the Dyer-Roeder equation in a cosmological model where creation of particles occurs at the expenses of the gravitational field. We discussed the influences of inhomogeneities in the path of a…

Astrophysics · Physics 2009-11-10 M. de Campos , J. A. Souza