Variations of the Cosmic Expansion Field and the Value of the Hubble Constant

Four Hubble diagrams are combined to test for the linearity of the cosmic expansion field. The expansion rate, H0, is found to decrease by ∼ 5% out to 18 000 km s. Beyond this distance the mean value of H0 is close to the value at 10 000 km s. The absolute value of H0 is derived in two different ways. The one leads through Cepheids from HST and blue SNe Ia to H0 = 57± 7 (external error) at 30 000 km s. The other uses various distance indicators to the Virgo cluster whose distance can be extended to 10 000 km s by means of only relative cluster distances; the result of H0 is closely the same. Independent distances from purely physical methods (SZ effect, gravitational lenses, and MBW fluctuations) cluster about H0 (cosmic)≈ 58.