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Physical meaning of wavefunction parameters x and t

  1. Jan 13, 2013 #1
    This isn't a homework question per se but it's a question that I had while reading through my textbook so I think it's appropriate here. I just started studying Quantum Mechanics and so am getting familiarized with the meaning of wave functions and their behavior. One question I can't seem to find the answer to no matter what keywords I use in Google is the following:

    What do the parameters of ψ(x,t) mean? When I imagine a 2D wave on a graph, I see a wave periodically going up and down along the x-axis, so parameter x (position). But the y-axis is not time, it's the amplitude. So where does the parameter 't' fit in to this graph?

    It feels like it should be a simple thing I should know but I do not and cannot find a good resource, so if anyone could help me understand its meaning, I'd appreciate it. Thanks1
  2. jcsd
  3. Jan 13, 2013 #2
    Oh and similarly, another thing I don't quite understand and that I can't find on the internet is:

    Where does the (kx-ωt) term come from in the wave function equation ψ(x,t) = ∫ A(k) e^i(kx-ωt) dk ? Essentially, I'm looking for a derivation of the wave function (typing that into Google somehow does not give me the right results).
  4. Jan 13, 2013 #3


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    Staff: Mentor

    Imagine the graph is animated so the wave moves from left to right (or from right to left). Then to see what the graph looks like at a particular time, substitute the appropriate value of t. Different values of t give you "snapshots" of the wave (ψ versus x) at different times.
  5. Jan 14, 2013 #4
  6. Jan 16, 2013 #5
    jtbell: Ahh, thank you for that clear image! That's what I was looking for.

    Sonderval: That is a pretty great blog you have there - I love that it's full of animations. I haven't gotten a chance to sit down and read it but I did skim over it and have added it to my Bookmarks to review when I get a free moment. Cool work!

    Thank you both for the help :)
  7. Jan 17, 2013 #6


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