A student has asked two question that I cannot answer and would appreciate
some help on:
1. If an ellipse is travelling at relativistic speed in a direction parallel
to its major axis, could it appear to a staionary observer as a perfect
circle? It would seem that the major axis could contract to equal the minor
axis but if the distance between the foci is also shrunk proportionally is it
not still an ellipse because they are not coincident?
2. If a disk moves past me at relativistic speed while it rotates about its
center at a constant angular velocity, what shape will I see? Since the top of
the disk is moving at a different speed relative to me than the bottom of the
disk, hwo does the different amount of contraction distort the disk from my
point of view.