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Wheeler's and Feynman's retarded and advanced waves.

  1. Jan 13, 2008 #1
    A while ago, Wheeler and Feynman published a cornerstone paper
    Interaction with the Absorber as the Mechanism of Radiation
    Rev. Mod. Phys. 17, 157 - 181 (1945)

    Briefly, there are two EM waves associated with accelerated charged particle, advanced and retarded waves. According common interpretation, the advanced wave has no physical meaning because of causality principle.

    Does anybody have an opinion different from above said about advanced wave?
     
    Last edited: Jan 13, 2008
  2. jcsd
  3. Jan 14, 2008 #2

    Andrew Mason

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    Feynman talks about this in his very entertaining Nobel lecture.

    He kind of jokes about the advanced wave concept:

    Andrew Mason
     
  4. Jan 16, 2008 #3
    Thanks, indeed entertaining lecture.
     
  5. Feb 6, 2009 #4
    Italian physicist Luigi Fantappiè had a dramatic insight into this phenomenon in 1941:

    “Suddenly I saw the possibility of interpreting a wide range of solutions (the anticipated potentials) of the wave equation which can be considered the fundamental law of the Universe. These solutions had been always rejected as “impossible”, but suddenly they appeared “possible”, and they explained a new category of phenomena which I later named “syntropic”, totally different from the entropic ones, of the mechanical, physical and chemical laws, which obey only the principle of classical causation and the law of entropy. Syntropic phenomena, which are instead represented by those strange solutions of the “anticipated potentials”, should obey two opposite principles of finality (moved by a final cause placed in the future, and not by a cause which is placed in the past): differentiation and non-causable in a laboratory. This last characteristic explained why this type of phenomena had never been reproduced in a laboratory, and its finalistic properties justified the refusal among scientists, who accepted without any doubt the assumption that finalism is a “metaphysical” principle, outside Science and Nature. This assumption obstructed the way to a calm investigation of the real existence of this second type of phenomena; an investigation which I accepted to carry out, even though I felt as if I were falling in a abyss, with incredible consequences and conclusions. It suddenly seemed as if the sky were falling apart, or at least the certainties on which mechanical science had based its assumptions. It appeared to me clear that these “syntropic”, finalistic phenomena which lead to differentiation and could not be reproduced in a laboratory, were real, and existed in nature, as I could recognize them in the living systems. The properties of this new law, opened consequences which were just incredible and which could deeply change the biological, medical, psychological, and social sciences.”

    It seems to me that with the recent fabrication of left handed materials, cloaking devices, and transformational optics, that its time to rethink the role that left-handed radiation might play in nature.
     
  6. Feb 6, 2009 #5
    Can't advanced waves be identified with the process of absorption? (The time-symmetric companion to radiation processes.)
     
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