International Astronomy and Astrophysics Research Journal

A Plausible Implication of the Universe Accelerated Expansion on Extragalactic Radio Source Luminosity

O. L. Ubah *

Nnamdi Azikiwe University, Awka, Nigeria.

J. C. Ezeugo

Nnamdi Azikiwe University, Awka, Nigeria.

*Author to whom correspondence should be addressed.

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Abstract

In this paper, statistical method of analysis was used to determine the variation of radio luminosity with cosmic epoch. Two different types of radio sources were used, radio-loud quasars and radio galaxies. They were used differently in order to ascertain consistency (if any) in their results. The results of the linear regression analyses obtained shows that the luminosity of extragalactic radio sources has an inverse power law function with the scale factor of the universe according to the relation, . The implication of this is that since the universe scale factor is time-dependent, the relation suggests that accelerated expansion of the universe causes diminution of radio source luminosity. This result suggestively indicates that extragalactic radio sources are more luminous at an earlier epoch than at a later epoch.

Keywords: Luminosity, quasars, galaxies, redshift, cosmic dilation, cosmic epoch, scale factor

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