Alternative Explanations of the Cosmic Microwave Background: A Historical and an Epistemological Perspective

TL;DR

This paper reviews historical and epistemological perspectives on non-conventional explanations for the cosmic microwave background, analyzing their merit, rejection dynamics, and implications for scientific orthodoxy and future ideas.

Contribution

It provides a comprehensive historical and philosophical analysis of alternative theories to the Big Bang and discusses their impact on scientific consensus and future research directions.

Findings

Many unorthodox interpretations have existed historically.

Orthodox Big Bang interpretation has gradually prevailed over decades.

Some alternative ideas remain plausible and may inspire future research.

Abstract

We historically trace various non-conventional explanations for the origin of the cosmic microwave background and discuss their merit, while analyzing the dynamics of their rejection, as well as the relevant physical and methodological reasons for it. It turns out that there have been many such unorthodox interpretations; not only those developed in the context of theories rejecting the relativistic ("Big Bang") paradigm entirely (e.g., by Alfven, Hoyle and Narlikar) but also those coming from the camp of original thinkers firmly entrenched in the relativistic milieu (e.g., by Rees, Ellis, Rowan-Robinson, Layzer and Hively). In fact, the orthodox interpretation has only incrementally won out against the alternatives over the course of the three decades of its multi-stage development. While on the whole, none of the alternatives to the hot Big Bang scenario is persuasive today, we discuss the epistemic ramifications of establishing orthodoxy and eliminating alternatives in science, an issue recently discussed by philosophers and historians of science for other areas of physics. Finally, we single out some plausible and possibly fruitful ideas offered by the alternatives.