Galaxy Colors in Distant Clusters as a Test for the World Model

The operational advantage of using colors of galaxies rather than magnitudes is that they are much less sensitive to deceleration parameter-dependent aperture corrections in photometry; in addition, their estimate is not strongly influenced by distance (as is the case for apparent magnitudes). A study is presently conducted of the colors of elliptical galaxies in nine distant clusters, with reference to theoretical models for evolutionary population synthesis. The admissible ranges of the relevant cosmological parameters are inferred.