Astronomy and Astrophysics – Astrophysics
Scientific paper
1996-11-14
Astronomy and Astrophysics
Astrophysics
16 pages, LaTeX(aaspp4), 11 postscript figures included; submitted to The Astrophysical Journal
Scientific paper
10.1086/304452
We investigate the cosmological test recently proposed by B. Fort, Y. Mellier and M. Dantel-Fort (FMD), where the observed location of the critical line in gravitational lensing is used to determine the cosmological parameters, $\Omega$ and $\lambda$. Applying this method to the cluster of galaxies Cl0024+1654, FMD obtained a constraint on the cosmological constant, $\lambda > 0.6$, assuming the spatially flat universe. It plays a crucial role in this method that the angular diameter distance-redshift relation depends on the cosmological models through the cosmological parameters. First, using the angular diameter distance in the Friedmann-Lemaitre- Robertson-Walker universe, we show that one can hardly determine $\Omega$ by this method without the assumption of the spatially flat universe. We also investigate the effect of inhomogeneities of the universe by using the Dyer-Roeder angular diameter distance. It is shown that the effect of inhomogeneities can become too large to be ignored, particularly for a high density universe. As a result, this method cannot be taken as a clear cosmological test to determine $\Omega$ and $\lambda$, though it may provide a bound on $\Omega$ and $\lambda$. Moreover, we mention the uncertainty of the determination of the velocity dispersion, which is regarded as one of the most serious problems in this test.
No associations
LandOfFree
Critical Lines in Gravitational Lenses and the Determination of Cosmological Parameters does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Critical Lines in Gravitational Lenses and the Determination of Cosmological Parameters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Critical Lines in Gravitational Lenses and the Determination of Cosmological Parameters will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-604917