Computer-modeled interference fringes and the subsequent analysis for re-evaluating the Michelson–Morley experiment

The Michelson–Morley experiment ignited a prolonged debate due to its unexpectedly small result. This study proposes an experimental simulation approach to investigate this phenomenon. All the testing steps can be performed on the computer, with the only exception of visual fringes replaced by positioning calculations. The findings made by this study demonstrate the following: (1) the derived light path difference differs from that achieved by actual adjustments; (2) the instrument’s rotation not only alters the light path difference between the two arms but also splits the coincidence between the two light beams; (3) adjustments performed with the instrument orienting in different directions generate different fringe-varying curves; and (4) using white light occasionally disturbs the fringe consistency during the instrumental rotations. When the latter three were combined, the M–M experiment could have encountered random irregular fringes during instrument rotations and diminished the fringe amplitude through repeated data averaging. Although the second-mentioned revelation implies correcting the current null interpretation, to address the first said limitation, the experiment chose not to measure fringes on the screen directly. Instead, it measured the distance in which the mirror was manually adjusted at each equidistant mark. This alternative method led to inaccurate or erroneous formation of the path difference due to inconsistent hand force and heat transfer, compromising the reliability of the original data. It is, therefore, recommended by this study that the Michelson–Morley experiment yielded indeterminate observational results.