The third way in which the explanation can be misleading is due to the nonlocal nature of a quantum state. Sometimes, two particles can be entangled, and then a distant measurement can be performed on one of the two. This measurement should not disturb the other particle in any classical sense, but it can sometimes reveal information about the distant particle. This restricts the possible values of position or momentum in strange ways.

— Wikipedia on Uncertainty principle

2011.01.07 Friday ACHK