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Related papers: Decaying $\Lambda$ cosmologies and statistical pro…

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We investigate some properties of flat cosmological models with a $\Lambda$ term that decreases with time as $\Lambda \propto a^{-m}$ (a is the scale factor and m is a parameter $0\leq m < 3$). The models are equivalent to standard…

Astrophysics · Physics 2009-10-30 V. Silveira , I. Waga

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

Upcoming ground and space based observatories such as the DES, the LSST, the JDEM concepts and the SKA, promise to dramatically increase the size of strong gravitational lens samples. A significant fraction of the systems are expected to be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Benjamin M. Dobke , Lindsay J. King , Christopher D. Fassnacht , Matthew W. Auger

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

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

Strong gravitational lensing has traditionally been one of the few phenomena said to oppose a large cosmological constant; many analyses of lens statistics have given upper limits on $\Omega_\Lambda$ that are marginally inconsistent with…

Astrophysics · Physics 2009-11-07 Charles R. Keeton

Significant adjustments to the values of the cosmological parameters estimated from high-redshift Type Ia Supernov\ae data are reported, almost an order of magnitude greater than previously found. They arise from the effects of weak…

Astrophysics · Physics 2009-10-31 Andrew J. Barber

For known gravitational lens systems the redshift distribution of the lenses is compared with theoretical expectations for $10^{4}$~Friedmann-Lema\^\i tre~cosmological models, which more than cover the range of possible cases. The…

Astrophysics · Physics 2011-05-23 Phillip Helbig , Rainer Kayser

Brane world cosmologies seem to provide an alternative explanation for the present accelerated stage of the Universe with no need to invoke either a cosmological constant or an exotic \emph{quintessence} component. In this paper we…

Astrophysics · Physics 2009-11-07 D. Jain , A. Dev , J. S. Alcaniz

Propagation of light in the universe with structure which amplify and modify the shape of distant galaxies, producing a correlation between nearby and distant density of galaxies, is a phenomena very important in cosmology for determining…

Astrophysics of Galaxies · Physics 2014-09-05 Leonardo Castañeda

Gravitational lensing has long been used to measure or constrain cosmology models. Although the lensing effect of gravitational waves has not been observed by LIGO/Virgo, it is expected that there can be a few to a few hundreds lensed…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-19 Shaoqi Hou , Xi-Long Fan , Zong-Hong Zhu

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 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

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

We present constraints on the cosmological constant lambda_0 and the density parameter Omega_0 from joint constraints from the analyses of gravitational lensing statistics of the Jodrell Bank-VLA Astrometric Survey (JVAS), optical…

Astrophysics · Physics 2007-05-23 J. F. Macias-Perez , P. Helbig , R. Quast , A. Wilkinson , R. D. Davies

The cosmological constant Lambda affects gravitational lensing phenomena. The contribution of Lambda to the observable angular positions of multiple images and to their amplification and time delay is here computed through a study in the…

Astrophysics · Physics 2008-11-26 M. Sereno

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

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

In this review, the status of measurements of the matter density (Omega), the vaccuum energy density or cosmological constant (Lambda), the Hubble constant (H0), and ages of the oldest measured objects (t0) are summarized. Measurements of…

Astrophysics · Physics 2009-10-30 Wendy L. Freedman
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