Say there is a circular fence that has a diameter of 10 meters, and a rocket ship that is normally 20 meters goes very quickly so that its relativistic length is 1m from the position of an observer standing at rest with relation to the fence.
The rocket ship starts to go in a circle inside the...
Say an electron is fired with the same De Broglie wavelength as blue light.
If the electron were to reach your eye, would you see blue, or would something else happen?