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A photon with spin 2?

  1. May 11, 2010 #1
    Dear all,

    Can you please enlighten me about the spin of photons?

    How can you tell if it is spin 1 or 2 ?

    Thanks,
    Alex
     
  2. jcsd
  3. May 11, 2010 #2
    1 since it transforms as a vector under lorentz transformations (or rather the four potential transforms as a vector)
     
  4. May 11, 2010 #3
    Dear ansgar,

    Can you explain the detection and nature of the four potential?

    "it" is the "four potential" that transforms as vector under Lorentz transformations?

    The spin is 1 because the vector is a tensor of order 1?

    Thanks,
    Alex
     
  5. May 11, 2010 #4
    yes vector = tensor rank 1

    http://en.wikipedia.org/wiki/Electromagnetic_four-potential

    Use google mate
     
  6. May 11, 2010 #5
    Dear ansgar,

    Thank you for your reply.

    What kind of tensor of rank 2 can you expect after a Lorentz transformation?

    Is the "four-potential" enough to describe the signals detected?

    cheers mate,
    Alex
     
  7. May 11, 2010 #6
    Assuming by "the signals" you mean the electric and magnetic fields, then it's more than enough (gauge freedom).
     
  8. May 11, 2010 #7
    Dear sheaf,

    Thank you for your kind reply.
    So the "four-potential" detects electric and magnetic fields.
    The matrix consider the electric and magnetic fields has independent signals?
    Is the magnetic field independent of the magnetic field?

    Cheers,
    Alex
     
  9. May 11, 2010 #8
    you mean

    Is the ELECTRIC field independent of the magnetic field?

    no you can see that from the very definition of E and B ...
     
  10. May 11, 2010 #9
    Dear ansgar,

    yes, I meant: Is the electric field independent of the magnetic field?
    thank you!

    cheers mate,
    Alex
     
  11. May 11, 2010 #10

    Vanadium 50

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    Afcarval, what's your background in physics. I get the impression that these answers aren't pitched at the level you're expecting.
     
  12. May 11, 2010 #11
    Dear Vanadium 50,

    In my degree I had some physics, in my master too and in my PhD also... but not specific in physics. Only a course in Quantum Monte Carlo...

    I had no expection about this forum pitch.

    My basic question: can you detect one photon with spin 2? Why?

    Thanks!
    Alex
     
  13. May 11, 2010 #12
    there is no such thing so how can you detect it?
     
  14. May 11, 2010 #13
    Dear ansgar,

    So you are telling me that by definition is not a photon?

    But can you model the response in order to have a photon with spin 2?

    Another way to put the question. Can you have a particule with spin 2 without electromagnetic perturbation?

    Why?

    Thanks,
    Alex
     
  15. May 11, 2010 #14
    you can detect photons with a combined angular momentum and spin and parity as you want, that is just the multipole expansion..
     
  16. May 11, 2010 #15
    Dear ansgar,

    Can you explain better?

    You are telling me that: if you want, you can detect a spin 2 for photons?

    Thanks,
    Alex
     
  17. May 11, 2010 #16
    you have not defined properly what you mean with all of this. photons can have angular momentum J which is the sum of L and S

    I can not explain better since what you really need is to define what and why you are asking this for and a couple of textbooks
     
  18. May 11, 2010 #17
    Dear ansgar,

    Thank you for your kind reply.

    One last question.
    In the detector and in the signal analysis can you tell the difference between a photon with spin 2 and a graviton?

    Cheers mate,
    Alex
     
  19. May 11, 2010 #18
    I kknow that there was some mumbo jumob behind all of this

    gravitions does not interact electromagnetically

    I am not your mate
     
  20. May 11, 2010 #19
    Dear ansgar,

    Mumbo jumob? They are simple questions...

    The question:
    Can you really have a particule with spin 2 without electromagnetic perturbation?
    Can you explain why?

    Or are they dogmas?

    Can I google it?

    cheers mate,
    Alex
     
  21. May 11, 2010 #20
    It seems that at some level you can model gravitons seem to be modeled by spin 2 particles.

    Not really.

    Observations. Some particles we see existing. Some particles we don't.
     
  22. May 11, 2010 #21
    Dear Twofish-quant,

    Thank you for your kind reply.

    Unfortunately I can not understand:
    "It seems that at some level you can model gravitons seem to be modeled by spin 2 particles."

    Can you explain? please.

    Thanks,
    Alex
     
  23. May 11, 2010 #22
    PARTICLES

    yes of course you can, just propose a tensor field of rank 2 and quantize it
     
  24. May 11, 2010 #23
    Dear ansgar,

    Thank you for your reply.

    Dirac did propose something like that...

    But then you have the other question.

    If you want, can you detect a "defined" photon with spin 2?

    Thanks,
    Alex
     
  25. May 11, 2010 #24
    defined photon.. what?
     
  26. May 11, 2010 #25
    Dear ansgar,

    0k, fair enough.

    Can I rephrase?

    If you want, can you detect a bosonic particle with spin 2?

    Thanks,
    Alex
     
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