Einstein’s awareness of the Michelson–Morley experiment during the drafting of the 1905 special relativity paper

Determine whether Albert Einstein was aware of the Michelson-Morley experiment at the time he composed his 1905 paper "On the Electrodynamics of Moving Bodies" (special relativity). Establish, using primary-source evidence such as correspondence, notebooks, lectures, and documented reading, the timing and nature of any knowledge Einstein had of Michelson-Morley prior to or during the drafting of this paper.

Background

Within the discussion of Einstein’s citations and experimental influences on the 1905 special relativity paper, the author highlights uncertainty about whether Einstein knew of the Michelson-Morley experiment when writing the paper, noting the absence of a citation. This question bears on the historiography of special relativity and the role that specific experiments may have played in its formulation.

The issue has been long debated, with inconsistent later recollections by Einstein and limited direct documentation linking him to Michelson-Morley before 1905. Resolving this requires careful analysis of contemporaneous materials—letters, reading notes, and other primary sources—to trace any concrete evidence of Einstein’s exposure to Michelson-Morley prior to or during the drafting of the 1905 paper.