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Is light composed of strings ?

  1. Jul 26, 2005 #1
    Is light composed of "strings"?

    I read Professor Michio Kaku book Hyperspace and have tried to
    create an online paper asking if light waves are composed of
    the elusive "strings" and if the light or strings could be manipulated
    without the energies required by Plank constant:


    I am a layman and have limited technical knowledge to understand
    replies Many thanks Chris Walters
  2. jcsd
  3. Jul 27, 2005 #2


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    It has been a while since I last read Hyperspace. (yes i have read it more than once)..
    I do enjoy reading about physics but am no physicist. (though I am trained in one of the applied areas "electrical engineering"). Therefore before sharing my opinions, lets address your question with a quote by Michio Kaku on the Theory of Everything I have italicized and highlit chosen words for emphasis.(follow the hyperlink to see his whole article)

    From his discussion, we may say that the same string vibrating in a different way (mode), generates a different fundamental particle (e.g. electron, quark, photon, graviton). Modes are fundamental patterns of vibration. Using this analogy it is clear how the same string can represent different particles.

    As a sidenote, we know photons behave not only as particles but also as waves. Varying the wavelength of light yields different frequencies (in the visible spectrum we perceive them as different colors). In Kaku's description, it is not apparent how the same string can represent different frequencies of light. My own thought is, perhaps light frequencies are expressed by a nonfundamental or complex vibrational mode (analogous to a complex wave in sound, such as a musical chord).
    Last edited: Jul 27, 2005
  4. Jul 27, 2005 #3


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    Perhaps instead of using the wave represention of photons it would help to use the particle representation. Then the color is proportionsal to the momentum of the particle. Now the vibration modes of the string carry, indeed are indexed by momentum - that is string momentum. But I could see how that momentum could effect the momentum of the particle generated by the mode.

    It has to be said here that the simple picture given by Kaku has never really generated a photon or any other common particle. Stringy attempts to do that are much more complex, involving many strings, as well as branes. These attempts have not really succeeded either, but they are continually getting closer.
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