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Constituents of pions

  1. Mar 23, 2009 #1
    The nucleon and antinucleon are each about seven times more massive than the pion How is it conceivable that the pion could be a combination of nucleon and antinucleon
  2. jcsd
  3. Mar 23, 2009 #2
    You are exactly correct, the pion is not made up of a nucleon and an antinucleon. The pion is a meson and is composed of a quark and an antiquark. In the case of a pion, it is made up of up and down (anti)quarks. Whether it is a positive, negative or neutral (electric) charged pion determines whether the up or down (or a linear combination) is quark or antiquark.

    You should consider picking up Griffiths "Introduction to Elementary Particles." It is an excellent book.
  4. Mar 23, 2009 #3
    What is conceivable, is to describe the nucleon as a chiral soliton in a pionic field, where the scalar and pseudoscalar Goldstone meson are treated as if elementary. Please note that this is a (convenient, powerful, elegant, appealing ?) model which neither ignores its own approximations (those fields are not fundamental) nor can not be at least partially justified from a more fundamental point of view. In particular, it attempts to treat spontaneous chiral symmetry breaking effectively.
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