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Are all of the quantum numbers of anti-particles opposite

  1. Apr 25, 2010 #1
    Hey

    Just wondering-

    Are all of the quantum numbers of anti-particles opposite to their corresponding particle quantum numbers?

    I know that lepton numbers are opposite for particles and anti particles
    As is charge.....

    But what about the quantum numbers like strangeness, spin, parity etc etc?

    Are they opposite too?

    Cheers
     
  2. jcsd
  3. Apr 25, 2010 #2

    clem

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    Science Advisor

    Re: Anti-Particles

    S is opposite.
    Spin and spin projection doesn't change.
    Parity is defined for the particle-antiparticle pair for fermions.
    It is negative for fermion-antifermion,
    Parity of an antiboson is the same as for the boson.
     
    Last edited: Apr 25, 2010
  4. Apr 28, 2010 #3

    blechman

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    Re: Anti-Particles

    i suppose the correct statement would be "antiparticles have negative INTERNAL quantum numbers". Here, the word "INTERNAL" means not spacetime.

    Examples of "internal QN": electric charge, strangeness, baryon number...

    Examples of "spacetime QN": mass, momentum, helicity...
     
  5. May 3, 2010 #4
    Re: Anti-Particles

    that's cleared a lot up, thanks guys :-)
     
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