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Constructing time-independent wave function with given energies

  1. Mar 30, 2008 #1
    Does anyone know how to construct a Time-independent wave function with given energies and probability on obtaining energies.
  2. jcsd
  3. Mar 30, 2008 #2


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    Are you asking about constructing an initial wave function, [tex]\Psi (x,0)[/tex], for a particle in a potential given that information?

    If so, what you are describing can be done by using the expansion theorem. Using that theorem, you can express a general time-independent wave function as an infinite sum of the energy eigenstates:

    [tex]| \Psi > = \sum_n^{\infty} C_n |n> [/tex]

    where [tex]|n> [/tex] is the wave function for the energy E_n and C_n is the probability for measuring that energy.

    I can't offer anything more specific given that information, but if you have a homework problem or something similar involving this, please post it in the homework help forum and I'll help you if I can.
    Last edited: Mar 30, 2008
  4. Mar 31, 2008 #3
    I found out the Coefficient expansion theorem and constructed the following wavefunction:

    Ψ(x,0) = 1/sqrt(2)*φ1 + sqrt(2/5)*φ3 + 1/sqrt(10)*φ5
    where φn = sqrt(2/a)*sin(n*pi*x/a)

    Is this unique why or why not? I'm thinking that it has something to do with all odd Energies.
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