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## Main Question or Discussion Point

Hi, I am having a hard time understanding the Lorentz - Fitzgerald contraction hypothesis (LFCH). I understand that it is a pre-relativity explanation of the null result of Michelson-Morley Experiment. My question is how did Lorentz derive the gamma factor, namely 1/sqrt(1-v^2/c^2), my understanding used to be that he used the results of Heaviside for the calculation of the electric field of point charge, which shows that the electric field of the point charge is contracted by gamma in the direction of motion, and therefore if we assume that the electrical forces dominates at the microscopic level then the length of any object is contracted by the gamma factor. This in turn will make the travel times in the two arms of the Michelson-Morley setup equal, thus yielding the null result.

My questions are:

1.The electric field of a moving point charge in the direction of motion will get contracted by (1-v^2/c^2) (Griffiths introduction to electrodynamics pg 439), and not by the gamma factor. So was my understanding of LFCH wrong? Basically how did Lorentz get the gamma factor? I am not asking for a full derivation, just the main results he used.

2.Is the LFCH based on the idea of absolute velocity? Because in the frame where the experiment was conducted the arms were not moving. But I keep reading that the arms get contracted in the direction of the motion. So motion relative to what? is it relative to the fame of the aether?

My questions are about the implications of the LFCH itself and not about what is right. I know that LFCH is wrong and there are experiments such that of Trounton-Rankine disproved it, if im not mistaken.

Thanks

My questions are:

1.The electric field of a moving point charge in the direction of motion will get contracted by (1-v^2/c^2) (Griffiths introduction to electrodynamics pg 439), and not by the gamma factor. So was my understanding of LFCH wrong? Basically how did Lorentz get the gamma factor? I am not asking for a full derivation, just the main results he used.

2.Is the LFCH based on the idea of absolute velocity? Because in the frame where the experiment was conducted the arms were not moving. But I keep reading that the arms get contracted in the direction of the motion. So motion relative to what? is it relative to the fame of the aether?

My questions are about the implications of the LFCH itself and not about what is right. I know that LFCH is wrong and there are experiments such that of Trounton-Rankine disproved it, if im not mistaken.

Thanks