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Compton effect and Photoelectric effect explained by wave theory?

  1. Feb 13, 2012 #1

    PrincePhoenix

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    I have the fifth edition of 'Physics' by Halliday, Resnick and Krane.
    In the chapter 'The Nature of Light' it is stated that it is possible to explain both photoelectric effect and Compton effect in classical electromagnetic wave theory and this has been known since 1927. It says that photoelectric effect was explicitly shown to be explainable by wave theory in 1969 by W.E. Lamb and M.O. Scully.

    http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680009569_1968009569.pdf

    It says that the experiment that really cannot be explained by the wave theory was conducted by J.F. Clauser in 1974 and then again corrected and performed by P. Grangier, G. Roger and A.Aspect in 1986.

    However when I searched the internet, I didn't get anything for Compton effect and read this
    https://www.physicsforums.com/showthread.php?t=372653

    on physics forums. Although both the paper and most of the discussion is beyond my level, I can sense most people don't agree with it.

    So what is the generally accepted view in this regard?

    Thanks in advance.
     
    Last edited: Feb 13, 2012
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  3. Feb 13, 2012 #2

    Jano L.

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    I think that what these people (Lamb, Jaynes,...) were trying to point out is that the modern quantization of the electromagnetic field (quantum optics) does not seem to be necessary to explain the gross features of these effects.

    Einstein introduced the concept of the light quantum but did not define it very well. After that, quantum theory of particles was developed, in which there is no light quantum - just classical electromagnetic field.

    Since the photoelectric effect is an effect stimulated by the _external_ field, there is a hope that it can be described by non-relativistic quantum theory with classical external field. The hope is there because similar thing is possible to do for the excitation of the atom; the time-dependent Hamiltonian containing the external electric field will cause the wave-function to change and the expectation value of its energy will rise.

    It is conceivable that the quantized behaviour of the photoelectric effect is due to the quantumness of the particles, while the radiation can be described by the wave theory. I think it is not ruled out that one can invent some kind of Hamiltonian that would give you the resonance behaviour of wave-function for bounded electrons at the right frequency. But I do not know whether Lamb or Jaynes really succeeded.
     
  4. Feb 13, 2012 #3

    ZapperZ

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    This paper might help you in clarification of this a bit

    http://people.whitman.edu/~beckmk/QM/grangier/Thorn_ajp.pdf

    Note also that other phenomena, such as photon anti-bunching, have no classical wave explanation.

    Zz.
     
  5. Feb 14, 2012 #4

    PrincePhoenix

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    I'm sorry I might have given wrong impression about my education level. I use the HRK for extra knowledge that I find interesting in my high school physics. I am actually only a high school student.
     
  6. May 3, 2012 #5
    I have couple of questions from Photo Electric Effect, if you could answer 1. why is the direction of photoelectric current opposite to the motion of electrons . 2. if we reduce deltaV to 0 photoelectric current doesnt drop to zero. why?
     
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