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

G. A. Tammann
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Abstract

Four Hubble diagrams are combined to test for the linearity of the cosmic expansion field. The expansion rate, H_0, is found to decrease by ~5% out to 18000km/s. Beyond this distance the mean value of H_0 is close to the value at 10000km/s. The absolute value of H_0 is derived in two different ways. The one leads through Cepheids from HST and blue SNe Ia to H_0=57+/-7 (external error) at 30000km/s. The other uses various distance indicators to the Virgo cluster whose distance can be extended to 10000km/s by means of only relative cluster distances; the result of H_0 is closely the same. Independent distances from purely physical methods (SZ effect, gravitational lenses, and MBW fluctuations) cluster about H_0(cosmic)=58.

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G. A. Tammann. 1998-05-04. Variations of the Cosmic Expansion Field and the Value of the Hubble Constant. https://arxiv.org/abs/astro-ph/9805013

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