EDDINGTON, ARTHUR STANLEY

(b. Kendal, United Kingdom, 28 December 1882;

d. Cambridge, United Kingdom, 22 November 1944), astronomy, astrophysics, relativity, science and religion. For the original article on Eddington see DSB, vol. 4.

Scholarship following the original DSB article provided new insights into Eddington’s educational background, his work in relativity and the 1919 eclipse expedition, his role in teaching and training physicists, his contributions to stellar physics, and the significance of his popular and philosophical writings.

Education . An important feature of Eddington’s education was his location in Manchester, which just before and during his time was the site of a movement known as the “Quaker Renaissance.” This involved a body of Quakers who argued that their religious tradition needed to embrace modernity. In particular, they sought harmonious relationships between religion and “modern thought” (largely science). Eddington was mentored by the leaders of this movement such as John William Graham, and their emphasis on values of mysticism, internationalism, pacifism, and civic engagement can be seen in many parts of Eddington’s career.

Relativity and the 1919 Eclipse Expedition . By the early 2000s, it was clear that Eddington’s advocacy of Albert Einstein and relativity was also a defense of internationalism in science, which he felt was seriously threatened by Great War jingoism. Eddington’s Quaker values of pacifism and internationalism made supporting Einstein’s theory a religious task as well as a scientific one, which helps explain why Eddington was virtually alone among British scientists in embracing German science during the war. He thus promoted the 1919 eclipse expedition as a landmark of scientific internationalism triumphing over war, in addition to its technical significance.

A controversial topic has been whether Eddington’s interest in relativity led him to manipulate the data of the expedition to provide a favorable outcome. This accusation of fraud usually rests on the rejection as unreliable of one of the three sets of data brought back in 1919. It is noted by critics that that discarded set was the only one of the three which did not support Einstein’s prediction, and Eddington is typically accused of a conspiracy to hide the unfavorable results. However, this claim ignores several important issues. First, the data were discarded because of optical problems during the eclipse observation in Brazil. These problems were noted in the field by the observers there (who did not include Eddington) long before the photographs were analyzed as being favorable or unfavorable to Einstein. Further, all three sets of data were made publicly available to the scientific community, and there were no objections from contemporary astronomers about the rejection of the corrupted data. Astronomers around the world were able to make their own measurements of the plates and agreed with Eddington’s analysis. It seems that the conspiracy theory is based on a misunderstanding of the optical techniques and data analysis methods in use at the time. Eddington’s contemporaries, well versed in the tacit knowledge involved in such difficult measurements, understood that the eclipse expedition results were well within the contemporary standards of scientific practice.

Teaching and Training . Historians interested in scientific training and pedagogy have examined Eddington’s difficulty in learning the technical details of general relativity without direct contact with Einstein. He took nearly two years to become skilled enough to make original contributions in the theory, even though he had significant advantages over most of his British colleagues: he had been taught differential geometry as an undergraduate, and was introduced to general relativity through Willem de Sitter, who had important experience in presenting Einstein’s theory in a comprehensible fashion. A tight relationship between Eddington’s pedagogy and his scientific work can be seen in the fact that Eddington’s first two books on relativity were almost certainly slight elaborations of his lecture notes for the first classes he taught on relativity. Virtually an entire generation of British scientists learned relativity from Eddington, and important aspects of his teaching can be traced through later developments in physics and astronomy.

Stellar Physics . Early twenty-first century historians of astronomy and physics have stressed that one of the difficulties Eddington encountered in his development of stellar models was that the physics of the day did not allow for a complete description of stellar interiors. This incompleteness led many physicists and astronomers holding to a deductive model of scientific truth to simply discard the problem as unworkable. For example, James Jeans argued that a physical model could not involve any unknown or partially understood agencies.

Eddington persevered and built a methodology on the idea that theories were pragmatic, approximate tools and did not need to be deductively certain. He constructed

his theoretical models on a variety of physical assumptions (often based on novel, hypothetical physics such as quantum mechanics), all designed to bring model and observation together as quickly as possible. Eddington argued that his method produced useful results (such as the mass-luminosity relation and the correct radii of stars) and avoided the sterile rigidity of the deductive approaches favored by his opponents. The debates over the sources of stellar energy provide a useful case study in the difficulty Eddington had in establishing his new theoretical astrophysics and in how he skillfully deployed cutting-edge work from both astronomy and physics.

Eddington’s later work in stellar physics led to his controversial exchanges with Subrahmanyan Chandrasekhar on the properties of dwarf stars and degenerate matter. The story has usually been told based on Chandrasekhar’s personal recollections and typically accuses Eddington of intentional cruelty and racist motivations in rejecting the Indian scientist’s theory. However, there is no evidence to suggest that this was the case. Eddington was famously vigorous in intellectual debate, and he treated Chandrasekhar just as he did his other rivals James Jeans and Edward Arthur Milne. Further, there is no reason to assume racism: for several years Eddington was the head of an organization which worked for Indian liberation.

Popular and Philosophical Writings . Eddington’s popular and philosophical works were analyzed closely by the early 2000s with respect to their cultural, intellectual, and social context. They were shown to not be completely idiosyncratic, but rather coherent parts of ongoing debates in interwar Britain. In the wake of the Great War, the cultural position of science was seriously contested.

Eddington’s popular books and lectures were designed to defend a liberal position in which science was perfectly compatible with traditional values, thus retaining both religion and science as critical elements of British identity and culture. He was particularly concerned with rejecting Marxist, materialist appropriations of science and their deterministic implications. However, he also rejected classical natural theology with its proofs of religion and rigid dogmatism. Eddington argued from a novel interpretation of positivism that religious experience and scientific experience were equally valid parts of human life, but that neither could prove any particular sectarian dogma. This ecumenical, reassuring position was quite popular in the interwar period with the last surge of liberal theology, but became less relevant with the death of that movement around World War II.

SUPPLEMENTARY BIBLIOGRAPHY

Bowler, Peter. Reconciling Science and Religion: The Debate in Early-Twentieth-Century Britain. Chicago: University of Chicago Press, 2001. Broad study of the relationship between science and religion in the interwar period.

Graham, Loren. Between Science and Values. New York: Columbia University Press, 1981. Chapters 2 and 3 discuss Eddington, particularly in contrast to Soviet expositors of relativity.

Hufbauer, Karl. “Astronomers Take up the Stellar-Energy Problem, 1917–1920.” Historical Studies in the Physical Sciences 11 (1981): 277–303.

Kenat, Ralph. “Physical Interpretation: Eddington, Idealization and the Origin of Stellar Structure Theory (Realism).” PhD diss., University of Maryland College Park, 1987.

Paul, Erich Robert. The Milky Way Galaxy and Statistical Cosmology. Cambridge, U.K.: Cambridge University Press, 1993. Discusses Eddington’s work in statistical cosmology.

Stanley, Matthew. “An Expedition to Heal the Wounds of War: The 1919 Eclipse Expedition and Eddington as Quaker Adventurer.” Isis 94 (2003): 57–89.

———. Practical Mystic: Religion and Science in the Life and Work of A. S. Eddington. Chicago: University of Chicago Press, 2007.

———. “So Simple a Thing as a Star: The Eddington-Jeans Debate over Astrophysical Phenomenology.” British Journal for the History of Science (2007).

Warwick, Andrew. Masters of Theory: Cambridge and the Rise of Mathematical Physics. Chicago: University of Chicago Press, 2003. Chapter 9 examines Eddington’s work on relativity in a pedagogical context.

Wilson, David. “On Removing ‘Science’ and ‘Religion’ from the Discussion of Science and Religion: The Cases of Eddington and Jeans.” In Facets of Faith and Science, edited by Jitse M. van der Meer. Lanham, MD: Pascal Centre for Advanced Studies in Faith and Science, University Press of America, 1996.

Matthew Stanley