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What is the origin of C,P and CP violations?

  1. Oct 26, 2012 #1
    The C and P symmetry violations are deduced from the separating the right-handed representation from left-handed representation in electroweak model(Weinberg theory).Then I do not understand why we can consider the left-handed fermions living in a representation separating with that of right-handed fermions if it is not because of neglecting the mass of fermions in weak interaction(can we neglecting the mass?)?

    The CP symmetry violation is deduced from the mixing three quark generations.Then I do not understand what allows the mixing of the three quarks?
  2. jcsd
  3. Oct 26, 2012 #2


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    AFAIK, mass is not neglected. The point is that electroweak interaction only couples to electrons and neutrinos of one handedness. If the particles are massive, Then the energy eigenstates are 50-50 superpositions of chiral eigenstates but the particles produced in weak interaction aren't energy eigenstates.
  4. Oct 26, 2012 #3


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    The mass eigenstates are different from the flavor eigenstates. If a specific flavor eigenstate is produced, it is a superposition of the mass eigenstates, and their relative phases change with time, giving components of other quarks.
    Alternatively, you can describe mixing as the exchange of (2) virtual W bosons.
  5. Oct 26, 2012 #4
    Why do you have to say their relative phase must be changed ''in time''?

    Please elaborate the explaining the mixing caused by exchange (2) virtue W.Is it correct if I think that one generation of quarks can transforms to other generation of quarks by exchange virtue W bosons?Then we can(?) consider different flavor quarks can ''combine with each other''.Then what is the condition for applying superposition principle?
  6. Oct 26, 2012 #5
    What suggests us about in electroweak interaction the fermions couple with only one handedness?
  7. Oct 27, 2012 #6


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    There was a classic experiment by Wu who observed polarisation in beta decay.
  8. Oct 27, 2012 #7
    Then what is the first theoretical idea about the handedness asymmetry?(I mean the motivate idea for the experiment)?
  9. Oct 27, 2012 #8


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  10. Oct 27, 2012 #9

    Vanadium 50

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    Last edited by a moderator: May 6, 2017
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