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I Particle in a 1D box system

  1. Oct 7, 2016 #1
    In the 1D particle in a box system why don't we take negative integer values of n besides the positive integer values? Well I thought about it and I think the reason is that during derivation we get ka=n (wavelength ) and thus n being negative implies that wavelength is negative hence contradiction.
  2. jcsd
  3. Oct 7, 2016 #2
    what is n?
    Iis it related to k= n.pi/L or n.pi/a if a is the width of the box
    moreover this condition is due to the acceptable wave function (solution of the Schrodinger equation) being zero at the boundary
    i.e. at x=0 and x=a

    and which dynamical variable is being quantised ?
    Is it energy state ?
    and if its energy ,then it may be proportional to n^2 rather than n.
  4. Oct 7, 2016 #3


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    Staff: Mentor

    Quantum states are uniquely defined up to a complex phase factor. What difference is there between ±n?
  5. Oct 7, 2016 #4


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    Staff: Mentor

    How does the wave function change for e.g. the second eigenstate if you replace n = +2 with n = -2? Does this make any difference in physically measurable quantities?
  6. Oct 8, 2016 #5
    Here we are considering the time independent Schrödinger equation.
  7. Oct 8, 2016 #6
    This may not make any difference in the physically measurable that is probability.
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