One of the widespread confusions concerning the history of the 1887 Michelson-Morley experiment has to do with the initial explanation of this celebrated null result due independently to FitzGerald and Lorentz. In neither case was a strict, longitudinal length contraction hypothesis invoked, as is commonly supposed. Lorentz postulated, particularly in 1895, any one of a certain family of possible deformation effects for rigid bodies in motion, including purely transverse alteration, and expansion as well as contraction; FitzGerald may well have had the same family in mind. A careful analysis of the Michelson-Morley experiment (which reveals a number of serious inadequacies in many text-book treatments) indeed shows that strict contraction is not required
We have shown that choosing a different set of postulates enables us to cancel the Lorentz Transformation (LT) from the main body of special relativity theory (SRT). Hence, this approach excludes the role of the relativistic length contraction, and, as a result, the Lorentz-Fitzgerald contraction hypothesis is only a consequence of using the Lorentz's real force (LF). We use the well-known examples to confirm that the relativistic length contraction is not required in relativistic electrodynamics.
The Fitzgerald-Lorentz hypothesis I have an affection for
The contraction of a moving body in the direction of its motion. In 1892 G. F. FitzGerald and H. A. Lorentz proposed independently that the failure of the Michelson-Morley experiment to detect an absolute motion of the Earth in space arose from a physical contraction of the interferometer in the direction of the Earth's motion. According to this hypothesis, as formulated more exactly by Albert Einstein in the special theory of relativity, a body in motion with speed υ is contracted by a factor in the direction of motion, where is the speed of light. ;