An international group of physicists has traced the origin of an electromagnetic interaction to the Dirac equation, a fundamental equation of quantum physics. The interaction couples the spin of the ...

Observing the effects of special relativity doesn't necessarily require objects moving at a significant fraction of the speed ...

This course introduces the quantum mechanical concept of angular momentum operator and its relationship with rotation operator. It then presents the angular momentum operators, their eigenvalues and ...

It is like jumping on and off a carousel: what happens to neutrons changing from a non-rotating frame of reference into a rotating frame of reference -- and back? 30 years ago, scientists predicted ...

It's almost always the last topic in the first semester of introductory physics—angular momentum. Best for last, or something? I've used this concept to describe everything from fidget spinners to ...