Reluctant Pioneer of Nuclear Astrophysics: Eddington and the Problem of Stellar Energy

TL;DR

This paper examines Eddington's early attempts to explain stellar energy through subatomic mechanisms, contrasting his approach with later nuclear physics theories and exploring why he did not pursue the nuclear route.

Contribution

It analyzes Eddington's historical work on stellar energy and investigates reasons for his divergence from nuclear physics developments in the 1930s.

Findings

Eddington proposed matter annihilation and helium synthesis as stellar energy sources.

He abandoned his early ideas as nuclear physics advanced.

His choices influenced the development of astrophysics theories.

Abstract

During the years from 1917 to 1921, A.S. Eddington was intensely occupied with Einstein's general theory of relativity and the epic eclipse expedition which confirmed one of the theory's predictions. During the same period, he investigated the old problem of why the stars shine, which led him to suggest two different subatomic mechanisms as the source of stellar energy. One of them was the annihilation of matter and the other the building-up of helium from hydrogen. This paper is concerned with Eddington's work in this area, a line of work to which he returned on and off during the 1920s but then abandoned. His decision to stop working on the stellar energy problem coincided with the first attempts to understand the problem in terms of nuclear physics and quantum mechanics. Why did Eddington not follow up his earlier work and why did he ignore the contributions of the nuclear physicists which in the late 1930s resulted in the first successful theories of stellar energy production?