Recent content by geelpheels

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    Undergrad How to derive orbital angular momentum of spins in quantum mechanics?

    How to derive orbital angular momentum of spins in quantum mechanics? Make up for some lost things in Griffiths QM 3rd Ed. Equation (4.134) in Griffiths QM 3rd Ed. was given but no explanation. Please explain how to derive this equation in detail or provide references that by reading them one...
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    High School If x2+y2+z2=xy+yz+zx prove x=y=z

    A much easier way, from x2+y2+z2=xy+yz+zx you can get 2x2+2y2+2z2=2xy+2yz+2zx which equals 2x2+2y2+2z2-2xy-2yz-2zx=0 ,the equivalent is (x-y)2+(y-z)2+(z-x)2=0.