Abstract

It is well known that before the redshift-magnitude diagram of galaxies could be used for determination of the cosmological parameters one must know the evolution of the galaxies. We propose use of apparent surface brightness: which depends only on the redshift and is independent of the cosmological model and the inhomogeneities in the universe: for observational determination of the evolution of galaxies. The needed observations are isophotal angular diameters and apparent magnitudes within this or any other reasonable angular diameter. The application of the results for determination of q/sub 0/ is discussed briefly. (AIP)