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The Michelson-Morley experiment was performed by Albert Michelson and Edward Morley¹. The experiment was to attempt to detect the relative motion of matter. The results were not as expected and were considered to be the first strong evidence against the aether theory. This was the start of the development of the theory of special relativity.

In 1881, Michelson invented a salutation to construct a sufficiently accurate device to detect aether flow. In 1885, Michelson began to collaborate with Edward Morley to confirm higher accuracy on Fresnel’s drag coefficient to improve Michelson’s 1881 experiment and to establish the wavelength of light as a standard of length². In 1886 they successfully confirmed Fresnel’s drag coefficient which was considered as a confirmation of the stationary aether concept. After the all the preparation the experiment has been referred to as the most famous failed experiment in history³. The experiment did not provide information of the properties of the aether. 

Michelson-Morley type experiments have been repeated with increasing sensitivity. In addition, recent resonator experiments have confirmed the absence of any aether wind. Through development of Ives-Stilwell and Kennedy-Thorndike experiments, fundamental tests of special relativity theory formed.




1. Michelson, Albert Abraham & Morley, Edward Williams (1887). "On the Relative Motion of the Earth and the Luminiferous Ether". American Journal of Science 34: 333–345.

2. Michelson, Albert Abraham & Morley, Edward Williams (1887). "On a method of making the wave-length of sodium light the actual and practical standard of length". American Journal of Science 34: 427–430.

3. Blum, Sergey V. Lototsky, Edward K.; Lototsky, Sergey V. (2006). Mathematics of physics and engineering. World Scientific. p. 98. ISBN 981-256-621-X., Chapter 2, p. 98


Michelson Morley Experiment

Show that the null effect of the Michelson Morley experiment can be accounted for if the interferometer arm parrallel to the motion is shortened by a factor of [1-(v/c)^2]^1/2.