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Related papers: Statistical evaluation of the observational inform…

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I present constraints on cosmological parameters in the lambda_0-Omega_0 plane from a joint analysis of gravitational lensing statistics (astro-ph/9904175) and the magnitude-redshift relation for Type Ia supernovae (astro-ph/9812133 and…

Astrophysics · Physics 2007-05-23 Phillip Helbig

We have developed a technique to systematically discover and study high-redshift supernovae that can be used to measure the cosmological parameters. We report here results based on the initial seven of >28 supernovae discovered to date in…

This work is related to different questions within cosmology. The principal idea herein is to develop cosmological knowledge making use of the analyses of observational data in order to find the values of the matter density Omega_m and…

Astrophysics · Physics 2007-05-23 S. M. Harun-or-Rashid

We compare and combine likelihood functions of the cosmological parameters Omega_m, h and sigma_8 from the CMB, type Ia supernovae and from probes of large scale structure. We include the recent results from the CMB experiments BOOMERANG…

Astrophysics · Physics 2007-05-23 S. L. Bridle

The knowledge of the redshift of multiple images in cluster-lenses allows to determine precisely the total projected mass within the Einstein radius. The observation of various multiple images in a same cluster is opening new possibilities…

Astrophysics · Physics 2007-05-23 G. Golse , J. -P. Kneib , G. Soucail

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

We use weighted mean and median statistics techniques to combine individual estimates of Omega_m0, the present mean mass density in non-relativistic matter, and determine the observed values and ranges of Omega_m0 from different…

Astrophysics · Physics 2009-11-07 Gang Chen , Bharat Ratra

Cosmic microwave background data shows the observable universe to be nearly flat, but leaves open the question of whether it is simply or multiply connected. Several authors have investigated whether the topology of a multiply connect…

Astrophysics · Physics 2009-11-07 Jeffrey R. Weeks

Recent observational results suggest that our universe is nearly flat and well modelled within a $\Lambda$CDM framework. The observed values of $\Omega_{m}$ and $\Omega_{\Lambda}$ inevitably involve uncertainties. Motivated by this, we make…

General Relativity and Quantum Cosmology · Physics 2009-11-10 B. Mota , M. J. Reboucas , R. Tavakol

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 perform a combined likelihood analysis of the latest cosmic microwave background anisotropy data and distant Type 1a Supernova data of Perlmutter etal (1998a). Our analysis is restricted to cosmological models where structure forms from…

Astrophysics · Physics 2009-10-31 G. Efstathiou , S. L. Bridle A. N. Lasenby , M. P. Hobson , R. S. Ellis

We were asked to debate the value of the cosmological mass-density parameter Omega. Is Omega_m=1 in accordance with the simplest model? Is Omega_m much smaller as indicated by some observations? There is conflicting evidence. We lay out the…

Astrophysics · Physics 2007-05-23 Avishai Dekel , David Burstein , Simon D. M. White

We investigate observational constraints from lensing statistics and high-z type Ia supernovae on flat cosmological models with nonrelativistic matter and an exotic fluid with equation of state, $p_x=(m/3 -1)\rho_x$. We show that agreement…

Astrophysics · Physics 2008-11-26 Ioav Waga , Ana Paula M. R. Miceli

The possibility of determining cosmological parameters on the basis of a wide set of observational data including the Abell-ACO cluster power spectrum and mass function, peculiar velocities of galaxies, the distribution of Ly-$\alpha$…

Astrophysics · Physics 2007-05-23 B. Novosyadlyj , R. Durrer , S. Gottloeber , V. N. Lukash , S. Apunevych

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

Most cosmological parameter estimations are based on the same set of observations and are therefore not independent. Here, we test the consistency of parameter estimations using a combination of large-scale structure and supernovae data,…

Astrophysics · Physics 2009-11-10 Carolina Odman , Mike Hobson , Anthony Lasenby , Alessandro Melchiorri

We report measurements of the mass density, Omega_M, and cosmological-constant energy density, Omega_Lambda, of the universe based on the analysis of 42 Type Ia supernovae discovered by the Supernova Cosmology Project. The…

Standard cosmological analyses typically treat galaxy formation and cosmological parameter inference as decoupled problems, relying on population-level statistics such as clustering, lensing, or halo abundances. However, classical studies…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-05 Kito Liao , Francisco Villaescusa-Navarro , Romain Teyssier , Natalí S. M. de Santi

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

We compare and combine likelihood functions of the cosmological parameters Omega_m, h and sigma_8, from peculiar velocities, CMB and type Ia supernovae. These three data sets directly probe the mass in the Universe, without the need to…

Astrophysics · Physics 2009-10-31 S. L. Bridle , I. Zehavi , A. Dekel , O. Lahav , M. P. Hobson , A. N. Lasenby
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