Question

Is length contraction due to the velocity affecting the molecular structure of the material?

Answer 1

Answer:

Yes and no. The length contraction of a macroscopic object could be well described as an optical illusion while the length contraction of the field of an individual particle seems rather real.

The reason for this is that after being accelerated, a bunch of charged particles will cast a shorter image on an electrode compared to the image cast by a similar bunch which had not been accelerated.