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

Quarks effective masses and the pions

  1. Oct 9, 2011 #1
    Hi everybody :)

    A lagrangian of the u and d quarks where they don't have a mass, shares chiral SU(2) and U(1) symmetries.
    In the vacuum, we write
    [itex] <0| \bar{Q} Q | 0 > = \eta [/itex]
    where Q is the douplet of u and d quarks. In such a way we break chiral symmetries.
    The current associated with the three axial broken symmetries creates three goldstone bosons, the pions, and in the approximation where d and u are massless, the pions are massless too.

    Now I just don't understand the following point: breaking the symmetry, we give a mass to u and d quarks, as Peskin says in pag. 669.
    How can these quarks and their relative antiquarks form the pions, which we said to be massless?
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted



Similar Discussions: Quarks effective masses and the pions
  1. Effective Mass (Replies: 1)

Loading...