Recent content by chrisd

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    Proving simultaneous eigenvectors for commuting operators

    Homework Statement In my quantum class we learned that if two operators commute, we can always find a set of simultaneous eigenvectors for both operators. I'm having trouble proving this for the case of degenerate eigenvalues.Homework Equations Commutator: [A,B]=AB-BA Eigenvalue equation:A...
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    QM: Infinite Square Well -a/2 to a/2

    Ah, that's the ticket. It's probably easier without using exponential form, but I was able to prove that A=B for odd n (giving me a cosine) and A=-B for even n (giving me a sine). Thanks!
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    QM: Infinite Square Well -a/2 to a/2

    I have read similar threads about this problem but I wasn't able to make progress using them. Homework Statement Consider an infinite square-well potential of width a, but with the coordinate system shifted so that the infinite potential barriers lie at x=\frac{-a}{2} and x=\frac{a}{2}...
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    Calculating Pendulum Drop Distance for 45 Degree Angle - Homework Help

    Sorry, but I'm still a little confused here... I see your experimental d, called dexp, at 45° is larger than your dexp at 90°. With the way I've defined d above, this should not be possible, so perhaps I do not understand the experiment correctly. Could you start at the beginning and describe...
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    Calculating Pendulum Drop Distance for 45 Degree Angle - Homework Help

    I would like to lend a hand but I am a little confused about the variables you are using. If I interpret correctly, L=length of pendulum string (0.44m) d=height of pendulum bob at θ=45° (unknown) r=difference between L and d (unknown) If this is the case you don't need to worry about...