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Related papers: Rethinking Lensing and Lambda

200 papers

We study the effect of the cosmological constant on the statistical properties of gravitational lenses in flat cosmologies (Omega_{0}+lambda_{0} = 1). It is shown that some of the lens observables are strongly affected by the cosmological…

Astrophysics · Physics 2009-10-30 Deepak Jain , N. Panchapakesan , S. Mahajan , V. B. Bhatia

We reanalyse optical gravitational lens surveys from the literature in order to determine relative probabilities in the $\lambda_{0}$-$\Omega_{0}$ plane, using a softened singular isothermal sphere lens model. In addition, we examine a…

Astrophysics · Physics 2007-05-23 Ralf Quast , Phillip Helbig

For a wide variety of cosmological models characterized by the cosmic mass density $\Omega_M$ and the normalized cosmological constant $\Omega_{\Lambda}$, we derive an analytic expression for the estimate of magnification cross-sections by…

Astrophysics · Physics 2008-11-26 Zong-Hong Zhu

We have identified seven (field) elliptical galaxies acting as strong gravitational lenses and have used them to measure cosmological parameters. To find the most likely value for Omega_m (= Omega_matter) and Lambda, we have used the…

Astrophysics · Physics 2009-10-28 Myungshin Im , Richard E. Griffiths , Kavan U. Ratnatunga

We re-analyze constraints on the cosmological constant that can be obtained by examining the statistics of strong gravitational lensing of distant quasars by intervening galaxies, focusing on uncertainties in galaxy models (including…

Astrophysics · Physics 2007-05-23 Yu-Chung N. Cheng , Lawrence M. Krauss

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 present new limits on cosmological parameters from the statistics of gravitational lensing, based on the recently revised knowledge of the luminosity function and internal dynamics of E/S0 galaxies that are essential in lensing…

Astrophysics · Physics 2009-10-30 Masashi Chiba , Yuzuru Yoshii

We present a forecast analysis on the feasibility of measuring the cosmological parameters with a large number of galaxy-galaxy scale strong gravitational lensing systems. Future wide area surveys are expected to discover and measure the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-19 Tian Li , Thomas E. Collett , Coleman M. Krawczyk , Wolfgang Enzi

The observed number counts of high-redshift galaxy candidates have been used to build up a statistical description of star-forming activity at redshift z >~ 7, when galaxies reionized the Universe. Standard models predict that a high…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. Stuart B. Wyithe , Haojing Yan , Rogier A. Windhorst , Shude Mao

In this paper we investigate the statistical properties of gravitational lenses for models in which a cosmological term decreases with time as $\Lambda \propto a^{-m}$, where $a$ is the scale factor and $m$ is a parameter ($0 \leq m < 3$).…

Astrophysics · Physics 2015-06-24 L. F. Bloomfield Torres , I. Waga

We study constraints that anticipated DEEP survey galaxy counts versus redshift data will place on cosmological model parameters in models with and without a constant or time-variable cosmological constant $\Lambda$. This data will result…

Astrophysics · Physics 2011-07-19 Silviu Podariu , Bharat Ratra

Kochanek (1992) suggested that the redshifts of gravitational lens galaxies rule out a large cosmological constant. This result was questioned by Helbig & Kayser (1996), who pointed out that selection effects related to the brightness of…

Astrophysics · Physics 2007-05-23 Phillip Helbig

The case for a flat Cold Dark Matter model with a positive cosmological constant $\Lambda$ has been recently strongly advocated by some theoreticians. In this paper we give the observers point of view to the light of the most recent…

Astrophysics · Physics 2007-05-23 B. Fort , Y. Mellier

Galaxy-scale strong gravitational lenses with measured stellar velocity dispersions allow a test of the weak-field metric on kiloparsec scales and a geometric measurement of the cosmological distance-redshift relation, provided that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Josiah Schwab , Adam S. Bolton , Saul A. Rappaport

The fraction of high-redshift sources which are multiply-imaged by intervening galaxies is strongly dependent on the cosmological constant, and so can be a useful probe of the cosmological model. However its power is limited by various…

Astrophysics · Physics 2009-10-31 Daniel J. Mortlock , Rachel L. Webster

The cosmological constant Lambda affects cosmological gravitational lensing. Effects due to Lambda can be studied in the framework of the Schwarzschild-de Sitter spacetime. Two novel contributions, which can not be accounted for by a proper…

Astrophysics · Physics 2009-02-23 M. Sereno

In a flat, k=0 cosmology with galaxies that approximate singular isothermal spheres, gravitational lens image separations should be uncorrelated with source redshift. But in an open k=-1 cosmology such gravitational lens image separations…

Astrophysics · Physics 2009-10-30 Myeong-Gu Park , J. Richard Gott

We derive new limits on the value of the cosmological constant, $\Lambda$, based on the Einstein bending of light by systems where the lens is a distant galaxy or a cluster of galaxies. We use an amended lens equation in which the…

Astrophysics · Physics 2009-11-13 Mustapha Ishak , Wolfgang Rindler , Jason Dossett , Jacob Moldenhauer , Chris Allison

Strong lensing has developed into an important astrophysical tool for probing both cosmology and galaxies (their structures, formations, and evolutions). Now several hundreds of strong lens systems produced by massive galaxies have been…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Shuo Cao , Zong-Hong Zhu

We investigate the potentiality of using strong lensing clusters to constrain the cosmological parameters Omega_m and Omega_lambda. The existence of a multiple image system with known redshift allows, for a given (Omega_m, Omega_lambda)…

Astrophysics · Physics 2009-11-06 G. Golse , J. -P. Kneib , G. Soucail
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