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Can maxwell's EM theory explain the photoelectric effect?

  1. Jun 7, 2010 #1
    i know that einstein explained it in terms of particles but can maxwells EM waves explain the photoelectric effect aswell?
  2. jcsd
  3. Jun 7, 2010 #2


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    This is a bit strange, because since the classical E&M theory was in existence long before the Einstein's photoelectric effect model, one would think that if the classical E&M theory at that time can already describe the photoelectric effect, the phenomenon won't be THAT big of a "puzzle" at that time, will it?

    Have you read anything about the http://galileo.phys.virginia.edu/classes/252/photoelectric_effect.html" [Broken]?

    Last edited by a moderator: May 4, 2017
  4. Jun 7, 2010 #3
    That depends what you mean by "the photoelectric effect." If you're simply asking whether classical EM predicts that shining light on a metal will cause it to emit electrons, the answer is yes. If you're asking whether classical EM can reproduce the particular properties of photoelectric emission that led Einstein to think about it in terms of particles of light, the answer is maybe, depending on what kind of quantum mechanical model you introduce for the metal. But, if you're asking whether classical EM can reproduce all properties of the photoelectric effect that have been observed through the present, the answer is no.
  5. Jun 8, 2010 #4
    In my opinion, no. The mechanism whereby the Maxwellian fields (which are continuous in space and time) interact with electric charge is via the Lorentz force law. In brief, the Maxwell/Lorentz force on charged particles occurs continuously in space and time. In Einstein's explanation of the photoelectric effect, the interaction between the field and a charged particle occurs impulsively, essentially at a given point in space/time. Of course the lame answer is that if the photoelectric effect did not introduce a new paradigm for field/particle interactions, then why did Einstein get the Nobel prize?
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