High redshift structures and the geometry of the universe
Author: Phillipps, S.
Source: Astrophysics and Space Science, Volume 240, Number 2, 1996 , pp. 241-247(7)
Abstract:The geometry of space at high redshifts is dependent on the value of the cosmological constant Λ (or its normalised contribution to the curvature of space, Λ_0). Here we investigate the prospects for constraining Λ_0 from the apparent dimensions of structures seen at very high z. As an example we consider the single highest redshift structure currently known, at z=3.4. We show that there can be substantial differences in apparent orientation, depending on the cosmological model assumed, in particular the radial stretching at high z can lead to structures inprobably well aligned with the line of sight if we (incorrectly) assume a large value of λ_0. In our example we are limited by the effect of the (unknown) dynamics within this cluster/supercluster. However, a suitably well defined, relatively small, sample of large structures at high z, along with a study of their velocity fields, may provide an alternative, and complementary, approach to the use of very large statistical samples as required by previously suggested methods.
Document Type: Regular Paper
Affiliations: Astrophysics Group, Department of Physics, University of Bristol, Tyndall Avenue, Bristol BS8 1TL
Publication date: 1996-01-01