Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Phonons and Photons

  1. Nov 19, 2011 #1
    What is the difference between the photon and the phonon ?
     
  2. jcsd
  3. Nov 19, 2011 #2

    tom.stoer

    User Avatar
    Science Advisor

    Photons are quanta (particles) of the electromanetic field; phonons are collective excitations (quasi particles) of lattices in condensed matter.
     
  4. Nov 19, 2011 #3
    Thank you.
     
  5. Nov 19, 2011 #4
    Photons can be also interpreted as quasi particles resulting from collective excitations. This is specially true in action-at-a-distance theory electrodynamics, where electromagnetic fields do not exist as material systems.
     
  6. Nov 19, 2011 #5

    tom.stoer

    User Avatar
    Science Advisor

    What do you have in mind? In QED photons are elementary particles, whereas phonons always consist of underlying structures.
     
  7. Nov 19, 2011 #6
    Do you mean something like a coherent state?
     
  8. Nov 20, 2011 #7
    In field-theoretic QED photons are the particles associated to the EM field. IN AAAD QED, there is not EM field and photons are quasiparticles
     
  9. Nov 20, 2011 #8
    I do not know what do you mean by coherent state, but I think is unrelated.
     
  10. Nov 21, 2011 #9

    tom.stoer

    User Avatar
    Science Advisor

    What is AAAD QED? Can you provide some explanations or references? How is this related to the original question which can be interpreted as a question regarding mainstream physics?
     
  11. Nov 21, 2011 #10
    AAAD = Action-At-A-Distance

    http://rmp.aps.org/abstract/RMP/v67/i1/p113_1

    Because your answer is only a half of the modern picture...
     
  12. Nov 21, 2011 #11

    tom.stoer

    User Avatar
    Science Advisor

    Sorry, my answer is approximately 99.999% of the modern picture; but what you propose is not 'the modern picture' at but definitly beyond standard (mainstream) physics. That does not mean that it's wrong, but it's definitly irrelevant for this thread and confusing for the OP.
     
  13. Nov 21, 2011 #12
    Agree with a systematic error of about a 75% in your number :rolleyes:.

    Agree again with you, the American Physical Society, and Reviews of Modern Physics are well-known non-mainstream resources :wink:.

    Yes, it is best to repeat semi-correct clichés, without being aware of modern avenues of research.
     
  14. Nov 21, 2011 #13

    tom.stoer

    User Avatar
    Science Advisor

  15. Nov 21, 2011 #14

    Cthugha

    User Avatar
    Science Advisor

    RMP is especially devoted to "recent work of interest to all physicists, especially work at the frontiers of physics" as the APS states. As such it is indeed also aiming at non-mainstream positions. For a RMP, 18 indexed citations in 16 years also mean more or less that the topic is certainly not mainstream.

    The stuff by Hoyle and Narlikar follows Wheeler's and Feynman's absorber theory and aims at steady-state cosmology which is in any way far from mainstream. It is somewhat correct physics (although difficulties with the microwave background given by WMAP results arise which might, however, be settled), but definitely not mainstream.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Phonons and Photons
  1. Phonon, anyone? (Replies: 3)

  2. Phonon Spectrum (Replies: 3)

Loading...