2001/04/04 by Abha Dev, Dev, Abha, Deepak Jain +8
Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics (astro-ph) #Cosmology and Gravitation Theories #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Geophysics and Gravity Measurements #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0104076
Modified results obtained by incorporating the correct use of selection function. Latex File, 6 Fig's., 39 pages
openalex publication_date 2001/04/04 · arxiv created 2001/10/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper, observational constraints on the cosmic equation of state of dark energy (p = w ρ) have been investigated using gravitational lensing statistics. A likelihood analysis of the lens surveys has been carried out to constrain the cosmological parameters Ωm and w. Constraints on Ωm and w are obtained in three different models of galaxy evolution: no evolution model (comoving number density of galaxies remain constant), Volmerange and Guiderdoni model and fast merging model. The last two models consider the number evolution of galaxies in addition to the luminosity evolution. The likelihood analysis shows that for the no-evolution case w ≤ -0.04 and Ωm≤ 0.90 at 1σ (68% confidence level). Similarly for the Volmerange & Guiderdoni Model the constraints are w ≤ -0.04 and Ωm ≤ 0.91 at 1 σ. In fast merging model the constraint become weaker and it allows almost the entire range of parameters. For the case of constant Λ (w =-1), all the models permit Ωm = 0.3 with 68% CL which is consistent with the value of Ωm inferred from various other cosmological observations.