"<a href=""https://www.youtube.com/watch?v=tueAcSiiqYA&amp;t=2h12m00s"">2:12:00</a> Saying Lorentz contraction is an illusion will cause confusion. While it is true that you don't contract when someone else sees you moving (that would cause real problems)", rather they see your space and time differently, and according to them: you <b>are</b> contracted.