Technology: The Relation Between the Reception of Relativity and Ether-drift Experiments in the '20s

By Roberto Lalli

Università degli Studi di Milano/Massachusetts Institute of Technology


The development and the reception of relativity theory, both special and general, is one of the most analyzed field of study about continuity and discontinuity in physics. In this context, an important historiographical question is: Which elements were perceived as continuous and which as discontinuous in the early reception of relativity?

One element of discontinuity was the dismissal of the concept of ether, which Einstein explicitly made in his 1905 paper. In fact, several physicists regarded this dismissal as the real change of Einstein’s special relativity theory with respect to the electromagnetic theories of late 19th century. After Eddington’s 1919 announcement about the confirmation of stellar deflection around the sun, several optical ether-drift experiments were performed in order to verify or disprove some predictions of relativity theory:

An accurate study of these experiments shows the different conceptual roots on which these experiments were conceived and how these differences affected the experimental equipment. The interconnection between theory and practice of these experiments led us to some considerations about the way in which relativity theory was perceived in the 20s.

Furthermore, an analysis of personal correspondence of some of the actors related to these experiments show the reaction to their results (in particular Miller’s) of some national scientific communities. The analysis of this reaction shows some national features of relativity’s reception.