# Lorentz derivation of length contraction in electrodynamics

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What Lorentz was able to show was that Maxwell's theory of electromagnetism predicted precisely this much longitudinal contraction.To get this result, Lorentz modeled matter composing a body as a large collection of electric charges, all held together in equilibrium by electric and magnetic forces. The equilibrium was disturbed if the entire object was set in motion. Moving electric charges create magnetic fields that in turn act back of electric charges. All these changes settle out into a new equilibrium configuration. What Lorentz could show was that new configuration consists in a contraction of the body in the direction of motion in just the amount needed to eradicate a possible result from the Michelson Morley experiment. My question is: is this derivation of length contraction considered to be sound and correct today? Are they treated in modern textbooks?

Length contraction was postulated by George FitzGerald and H.A Lorentz (1892) to explain the negative outcome of the Michelson–Morley experiment and to rescue the hypothesis of the stationary aether .

It was considered an ad hoc hypothesis, because at this time there was no sufficient reason to assume that intermolecular forces behave the same way as electromagnetic ones.

Eventually, Albert Einstein (1905) was the first to completely remove the ad hoc character from the contraction hypothesis, by demonstrating that this contraction did not require motion through a supposed aether, but could be explained using special relativity, which changed our notions of space, time, and simultaneity.

Now a days the special theory of relativity and Lorentz Transformations are used to derive contraction as a consequence of STR.
one can see details of historical development in <https://en.wikipedia.org/wiki/Length_contraction> [Broken]

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Length contraction was postulated by George FitzGerald and H.A Lorentz (1892) to explain the negative outcome of the Michelson–Morley experiment and to rescue the hypothesis of the stationary aether .

It was considered an ad hoc hypothesis, because at this time there was no sufficient reason to assume that intermolecular forces behave the same way as electromagnetic ones.

Eventually, Albert Einstein (1905) was the first to completely remove the ad hoc character from the contraction hypothesis, by demonstrating that this contraction did not require motion through a supposed aether, but could be explained using special relativity, which changed our notions of space, time, and simultaneity.

Now a days the special theory of relativity and Lorentz Transformations are used to derive contraction as a consequence of STR.
one can see details of historical development in <https://en.wikipedia.org/wiki/Length_contraction> [Broken]