SPIN

What is spin? And how is it possible
Spin and events. What is the relation.
How do you know that something is spinning.
What quantum theory says about spin.

100% symmetrical object cannot spin. Because how it is possible for an observer to know that it is spinning?it might have other qualities butnot spin. Consider the two cases, as spinning ball with a polished surface and another like a golf ball that have identical dimples. An observer may not know that the polished ball is spinning, but will know that the ball with dimples spin. How does he know that.   He will see light reflected by dimples, changing and will come to the conclusion that the ball is spinning.