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Feynman- Radiation Resistance

  1. Jun 5, 2008 #1

    I was just reading feynman's nobel lecture the other day ("The Development of the Space-time view of qed") where he discusses the problems associated with his initial view that an electron does not act on itself but merely acts on other electrons. He talks about the "force of radiation resistance", this is shown below:

    Then I went to graduate school and somewhere along the line I learned what was wrong with the idea that an electron does not act on itself. When you accelerate an electron it radiates energy and you have to do extra work to account for that energy. The extra force against which this work is done is called the force of radiation resistance. The origin of this extra force was identified in those days, following Lorentz, as the action of the electron itself. The first term of this action, of the electron on itself, gave a kind of inertia (not quite relativistically satisfactory). But that inertia-like term was infinite for a point-charge. Yet the next term in the sequence gave an energy loss rate, which for a point-charge agrees exactly with the rate you get by calculating how much energy is radiated. So, the force of radiation resistance, which is absolutely necessary for the conservation of energy would disappear if I said that a charge could not act on itself.

    I was a little confused as to what he meant here and what this force of radiation resistance really is. I would appreciate it if someone could explain this to me, both the mathematics behind it and the physical interpretation and also why this created problems for the idea that an electron does not act on itself. Thanks a lot
  2. jcsd
  3. Jun 6, 2008 #2
    For a brief discussion of this topic, in classical terms, see The Feynman Lectures on Physics, Volume II, chapter 28 Electromagnetic Mass - especially sections 28-4 and 28-5.

    If you google for 'electron self-energy' you may find some useful links.
  4. Jun 7, 2008 #3
    ok thanks, i have the feynman lectures so ill read up on it :)
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