 :I'll post more links as I find them but here is something, sorry if it seems weak: http://www.physics.brocku.ca/People/Faculty/Sternin/teaching/mirrors/qm/stern-gerlach/index.html :>Why would silver atoms move in a sinusoidal path in a magnetic field? :Because of wave particle duality.  Wave has magnetic field component that oscillates up and down. :  