Expected differential phase shift between light traveling the longitudinal <i>versus</i> the transverse arms of the <a href="https://en.wikipedia.org/wiki/Michelson-Morley_experiment" class="extiw" title="en:Michelson-Morley experiment">Michelson–Morley</a> apparatus.
<a href="https://en.wikipedia.org/wiki/User:Stigmatella_aurantiaca" class="extiw" title="wikipedia:User:Stigmatella aurantiaca">Stigmatella aurantiaca</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>
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