Cosmological lore—and some heresies

Abstract

Cosmology is based on a number of well-founded assumptions, which include Hubble's law and the cosmological principle. Most cosmologists and astronomers also tacitly accept a number of other assumptions and beliefs which constitute a sort of traditional cosmological lore. Among these are the notions that the universe is finite, that if it is not, then there must be an observational horizon which renders it finite for all practical purposes, that it is valid to employ the special relativistic Doppler formula to interpret large cosmological redshifts, and that the expansion of the universe is slowing down toward its ultimate reversal. It is argued that none of these notions is incontrovertible and that some of them involve serious inconsistencies. An alternative approach is proposed which assumes that the universe is expanding uniformly and that it constitutes a fundamental reference frame for light propagation as implied by the Robertson-Walker metric. This approach leads to a model of the universe which is possibly infinite but without a specific observational horizon, and which satisfies the requirements of relativity. It is shown that the proposed model is theoretically consistent and that recent astronomical evidence supports its assumptions and predictions; it therefore presents a serious challenge to commonly held views about the universe.