On the role of the Michelson-Morley experiment: Einstein in Chicago

TL;DR

This paper explores Einstein's awareness of the Michelson-Morley experiment before 1905, analyzing new historical material to understand its influence on his development of special relativity.

Contribution

It presents new historical evidence from Einstein's 1921 Chicago lecture, clarifying his early knowledge and the experiment's impact on his thinking.

Findings

Einstein mentioned the Michelson-Morley experiment in 1921.

He was aware of the experiment before 1905.

The paper explains the contrast with his later views.

Abstract

This article discusses new material, published in Volume 12 of the Collected Papers of Albert Einstein, that addresses Einstein's knowledge of the Michelson-Morley experiment prior to 1905: in a lecture in Chicago in 1921, Einstein referred to the experiment, mentioned when he came upon it, and hinted at its influence. Arguments are presented to explain the contrast with Einstein's later pronouncements on the role of the experiment.