Speed and Aberration of Light and Redshift

Abstract

Musa D. Abdullahi

Relativistic constancy of speed of light, makes lightspeed a constant for all observers stationary or moving. This is despite discoveries of Aberration of Light in 1784 and Doppler Shift in 1842, which showed relativity of lightspeed. If the speed were constant, relative to everybody, it would have been found as infinitely large. But it was measured as very high and finite. Light adjusting its speed, to be same c for every moving observer, is untenable. This paper, invoking aberration of light, shows that speed of light depends on motions of source and observer and that speed of light, relative to the source, is a constant c. It gives rise to Doppler Shift in light. Redshift of starlight is ascribed to reduction in speed of light, due to refractions in intergalactic pathlength L for reaching the Earth. Hubble-Lemaître law, in physical cosmology, is deduced without an expanding Universe.

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