The Mass‐to‐Light Function: Antibias and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{emp

Analysis of Two Quintessence Models with Type Ia Supernova Data

“…m0 Our main results are summarized in Table 1. We observe that our results are in very good agreement with the one found in Bahcall et al (2000) in a completely independent way and that the high degeneracy we get for the model parameters seems to support the opinion of those who claim that it is very difficult to discriminate among theories on the basis of observational data only (Maor, Brunstein, & Steinhardt 2001 ;Barger & Marfatia 2000). The fact that some parameters are left completely free and others are found with large degeneracy also seems to indicate that there is no Ðne tuning with regard to initial conditions.…”

Antibias in Clusters: The Dependence of the Mass-to-Light Ratio on Cluster Temperature

“…Q m Observations of galaxies, groups, and clusters of galaxies show that the function increases with scale up to a few M/L hundred kpc (Rubin & Ford 1970;Roberts & Rots 1973;Ostriker et al 1974;Einasto, Kassik, & Saar 1974;Davis et al 1980;Zaritsky et al 1993;Fischer et al 2000) but then flattens on larger scales (Bahcall et al 1995;Fischer et al 2000). A comparison with high-resolution cosmological simulations (Bahcall et al 2000) reveals an excellent agreement with the observed function: the simulated function increases M/L M /L with scale on small scales (!0.5 Mpc) and flattens to a mean constant value on large scales, as suggested by the data.…”

“…Bahcall et al (2000) show that the antibias exists M/L in simulated clusters of galaxies: higher density clusters (richer, higher mass and temperature clusters) should exhibit larger ratios (especially in the blue and visual luminosity bands) M/L than poorer, lower mass and temperature clusters. The expected effect is a factor of approximately 2 increase from poor to rich clusters.…”

The Void Phenomenon

“…4.2. V oids in a L ow-Density Universe If the observations are consistent with ) m \ 0.25^0.1, the assumption that ordinary optically selected galaxies trace the mass (Bahcall et al 2000 and references therein). If galaxies are good mass tracers, we can assume the voids contain little mass.…”