Recent content by harrydent

Maybe someone could just explain it in plain English rather than a proof?

I'm reading from my textbook "Foundations of Quantum Physics," and came across a statement that sounds trivial but I don't know how to prove. The passage can be found at http://books.google.com/books?id=3rxOHtn85qcC&pg=PA289#v=onepage&q=&f=false". Does anyone have any information on the...