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Destructive wave interference

  1. Jul 5, 2007 #1
    I would like to touch a problem of the destructive wave interference and my main confusion is that for a mentioned phenomena the energy conservation law is not satisfied . A common answer is that a destructive interference is always followed by the constructive one and so... there is no problem, but what if I have a device where only the destructive interference is made and a signal applied to its input is just disappear without being converted in heat or in any other type of energy...???? such a device can be made with a simple electromagnetic resonator and with some additional circuits that eliminate reflections and in such way all the applied signal energy is just disappear inside the resonator...
    And my question is how to explain such a situation with the energy???? Any suggestions...
  2. jcsd
  3. Jul 6, 2007 #2


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    I don't think it'd be possible to construct such a device.

    Usually, waves always have regions of constructive and destructive interference. So, interference would distribute the energy of the wave into the zones of constructive and destructive interference, and the total energy will be conserved.
  4. Jul 8, 2007 #3

    Claude Bile

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    Two things will happen either;

    a) The input light will be reflected - e.g. Bragg gratings, high-reflection dielectric stacks.
    b) The atoms comprising the source will have their radiation suppressed - e.g. Fluorescent sources embedded inside photonic crystals.

  5. Jul 9, 2007 #4
    well, actually I suppose this device to work at microwave region and in this case it is possible to make such a resonator configuration where the signals reflected from resonator are canceled by the signals transmitted through it and the result is that you have a device that have no signal in its outputs and does not have any reflected waves and apart from that there is no electromagnetic fields inside the resonator but it consumes power from the source generator and this generator could have saying 100W of power but
    all the device loads and the resonator are not even warm...sure the same trick can be made at the optical frequencies...
  6. Jul 9, 2007 #5

    Claude Bile

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    You will probably find that the power will go into generating non-resonant frequencies.

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