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Related papers: Beyond lensing by the cosmological constant

200 papers

The general idea of determining cosmological parameters with gravitational lensing statistics is outlined, and then recent work---with an emphasis on applicability to all cosmological models, observational bias, better statistics and…

Astrophysics · Physics 2011-04-15 Phillip Helbig

These lectures give an introduction to Gravitational Lensing. We discuss lensing by point masses, lensing by galaxies, and lensing by clusters and larger-scale structures in the Universe. The relevant theory is developed and applications to…

Astrophysics · Physics 2009-09-25 Ramesh Narayan , Matthias Bartelmann

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 present limits on the cosmological constant from the statistics of gravitational lenses using newly completed quasar surveys, new lens data, and a range of lens models. The formal limit is $\lambda_0 < 0.66$ at 95\% confidence in flat…

Astrophysics · Physics 2009-10-28 C. S. Kochanek

We give an estimate of the gravitational field of force exerted on a test particle by the far galaxies, in the frame of the weak field approximation. In virtue of Hubble's law, the action of the far matter turns out to be non negligible,…

Astrophysics · Physics 2011-11-10 A. Carati , S. L. Cacciatori , L. Galgani

We give a non-exhaustive review of the use of strong gravitational lensing in placing constraints on the quantity of dark and visible mass in galaxies. We discuss development of the methodology and summarise some recent results.

Astrophysics · Physics 2009-11-13 Simon Dye , Steve Warren

If the gravitational lens is surrounded by non-homoheneous plasma, in addition to the vacuum gravitational deflection, chromatic refraction occurs. Also, the speed of signal propagation decreases compared to vacuum. In this article, we…

General Relativity and Quantum Cosmology · Physics 2023-07-12 Gennady S. Bisnovatyi-Kogan , Oleg Yu. Tsupko

The exploration of the redshift drift, a direct measurement of cosmological expansion, is expected to take several decades of observation with stable, sensitive instruments. We introduced a new method to probe cosmology which bypasses the…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Chengyi Wang , Krzysztof Bolejko , Geraint F. Lewis

The specified constant 4-vector field reproducing the spherically symmetric stationary metric of cold dark matter halo in the region of flat rotation curves results in a constant angle of light deflection at small impact distances. The…

General Relativity and Quantum Cosmology · Physics 2009-11-11 V. V. Kiselev , D. I. Yudin

Compact objects with magnetic dipole are considered as gravitational lenses. The presence of strong magnetic field near the photon sphere can affect the trajectory of light. We compute the deflection angle near the photon sphere on the…

General Relativity and Quantum Cosmology · Physics 2025-09-03 Jin Young Kim

We study gravitational lensing by clusters of galaxies in the context of the generic class of unconventional gravity theories of the scalar--tensor type. For positive energy scalar fields with any dynamics, the bending of light by a weakly…

Astrophysics · Physics 2010-11-01 Jacob D. Bekenstein , Robert H. Sanders

Recently, Rindler and Ishak have argued that the bending of light is, in principle, changed by the presence of a cosmological constant since one must consider not only the null geodesic equation, but also the process of measurement. I agree…

General Relativity and Quantum Cosmology · Physics 2007-11-27 Kayll Lake

We discuss the influence of the cosmological constant $\Lambda$ on the gravitational equations of motion of bodies with arbitrary masses and eventually solve the two-body problem. Observational constraints are derived from measurements of…

Astrophysics · Physics 2009-11-13 Philippe Jetzer , Mauro Sereno

We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space-time curvature, predicts the existence of halos of modified gravity surrounding…

General Relativity and Quantum Cosmology · Physics 2009-03-20 Kirill Krasnov , Yuri Shtanov

After a brief introduction to gravitational lensing theory, a rough overview of the types of gravitational lensing statistics that have been performed so far will be given. I shall then concentrate on recent results of galaxy-galaxy…

Astrophysics · Physics 2021-04-28 Norbert Straumann

Associated with the cosmic acceleration are the old and new cosmological constant problems, recently put into the more general context of the dark energy problem. In broad terms, the old problem is related to an unexpected order of…

Astrophysics · Physics 2008-11-26 Mustapha Ishak

We examine models of the mass distribution for the first known case of gravitational lensing. Several new sets of constraints are used, based on recent observations. We remodel the VLBI observations of the radio jets in the two images of…

An analysis of null geodesics in Schwarzschild de Sitter space is presented with special attention to their global `bending angles', local measurable angles, and the involvement of the cosmological constant. We make use of a general…

General Relativity and Quantum Cosmology · Physics 2016-09-19 Dmitri Lebedev , Kayll Lake

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

Gravitational and plasma lensing share the same mathematical formalism in the limit of geometrical optics. Both phenomena can be effectively described by a projected, two-dimensional deflection potential whose gradient causes an…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner , Xinzhong Er