There was a young fencer named Fisk,
whose movements were exceedingly brisk.
So fast was his action, the Lorentz Contraction
diminished his sword to a disk.
The Lorentz-Fitzgerald contraction is the contraction in length of a moving body, as measured by an observer at rest with respect to the body, by the factor 1/√(1 - ν2/c2), where ν is the relative speed of the moving body and c is the speed of light. Also called the Lorentz contraction or Fitzgerald contraction – the theory was proposed independently by both Hendrik Lorentz and George Fitzgerald – it one of the surprising effects predicted by Einstein's special theory of relativity. Compare with time dilation.