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Peskin, problem 19.1

  1. Oct 27, 2012 #1
    Hi,
    I'm trying to do this problem (19.1 from Peskin) that apparently should be quite straightforward but when I plug the anzat given at c) into the equation I don't get an harmonic oscillator as the book indicates. Could please anyone tell me what is wrong?
    Thanks
     
  2. jcsd
  3. Oct 27, 2012 #2

    Vanadium 50

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    This is a first - not only does the student not type the answer, he doesn't even type the question!
     
  4. Oct 27, 2012 #3
    I think the question/problem is quite clear: The problem 19.1 from the peskin QFT book. I give as a fact that anyone in the high energy physics section has acces to this book to refer to the problem.
    Anyway the problem is the following:
    given the equation [tex] -i \sigma \cdot D \psi_R=0, [/tex] where [tex]A^{\mu}=(0,0,B x^1, A) [/tex] with [tex] B [/tex] a constant and [tex]A[/tex] depends only adiabatically in time.
    Now when I put the anzat given by the book [tex]\psi_R=\left(\begin{array}{c}\phi_1(x^1)\\ \phi_2(x^1)\end{array}\right)e^{i(k_2x^2+k_3 x^3)}[/tex] and eliminate one of the [tex] \phi [/tex] I'm supossed to get an harmonic oscillator eqn. How? I get an eqn of the form [tex] \phi_i ''(x^1)+\omega^2(x^1) \phi_i(x^1)=0 [/tex] with an explicit dependence of [tex]\omega[/tex] in [tex]x[/tex].
     
  5. Oct 27, 2012 #4

    Vanadium 50

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    Not everyone is within arm's reach of Peskin. I don't even own a copy.
     
  6. Oct 28, 2012 #5

    mfb

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    You get a harmonic oscillator at every ##x^1##, where the frequency depends on that coordinate.

    By the way: with [itex]-tags, you don't get new lines for every symbol.
     
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