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Virtual Particles and Photons

  1. Apr 15, 2013 #1
    We know electric current travels around 200000 km/s.. Yet electrons are moving way much slower, just acting as a medium for the transportation of the energy.

    Can same principle apply for light? Although the energy flows at 300000 km/s the photons may actually not? Like, the energy traveling on a medium made of virtual photons, that in certain states comes to being and observed.

    Since photons are particle like, and wave like. Are there any studies answering how this is so?

  2. jcsd
  3. Apr 15, 2013 #2
    We can perform experiments with single photons, and we observe that they travel at the speed of light.

    On the theoretical side, there are many issues with slow photons. For example, special relativity would require them to have nonzero rest mass, despite experiments (such as Coulomb's Law and precision QED) that indicate otherwise.
  4. Apr 16, 2013 #3
    Can you point me to an experiment you had in mind as an example?

    I am not sure if we can actually observe a photon, i would suggest like in my original post, that all we might observe is the fluctuations the energy creates in vacuum. Thus, virtual photons gains an extremely short life existence, probably undetectable.

    Also, we do know photon is a rare particle. Antiphotons and photons are actually the same thing in the end. One might also suggest that, you can only observe the photon that had left the source once you actually try to observe it. It doesn't mean that photon came there at speed c. You can't even know which particle you have actually captured through the fluctuations, the photon or its antiphoton. Since they are the same thing anyway..

    I want to see if the experiment you have in mind can disprove the above idea.
  5. Apr 16, 2013 #4


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    The photon is a fluctuation of the electric and magnetic field, and we know that these fluctuations propagate at c. Now, if you are talking about a fluctuation propagating through a medium of photons, now you are talking about a fluctuation made up of fluctuations, which is just silly.
  6. Apr 16, 2013 #5
    You have to note that, I got two answers to the same question.

    Does photon travel at the speed of light?
    Is it the fluctuations of the electric and magnetic field that travel at c?
    Do we call these fluctuations of the electric and magnetic field that travel at c, photons?
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