The Michelson-Morley Interferometer Experiment of 1887 is often cited as one of the cornerstones (and perhaps THE cornerstone) upon which Einstein built his theory of special relativity. Allegedly, it “proved” there was no aether. Once Einstein postulated that the speed of light was invariant, the only explanation that became accepted was that time slowed and length contracted due to relative motion according to the Lorentz Transformation formulae, adopted by Einstein as tenets of his special relativity. Despite subsequent experiments contradicting the alleged “null result,” reanalysis of the results indicating positive (“non-null”) results, and even maintaining the validity of the null result but explaining it via classical physics, the M&M Interferometer Experiment remains a special relativity foundation. However, if the limitation of the invariance of the speed of light is removed, the “null result” can be easily explained without resort to special relativity and its postulates of time dilation and length contraction. Yet this is seldom done.
