The broad acceptance of the expansion of the universe as a physically real phenomenon has been rooted in part in the apparent lack of an alternative explanation of the redshift. Since its discovery more than a half-century ago, many new observational phenomena have been uncovered, of which quasars and microwave background adiation appear to be particularly fundamental and striking. Nevertheless, there seem to have been few attempts to rework the foundations of cosmology in a way that might tie these phenomena together in a scientifically more economical way. This is probably due more to the momentum of the theoretical studies based on the expansion theory than to its agreement with observation, which has been quite limited and increasingly equivocal.
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