Self-explaining question... Thanks.
in which context?
As an alternative to Feynman diagrams (?), or so I heard...
It doesn't sound ok, right?
no then it just means a feynman diagram "on quark level" eg. beta decay
It seems reasonable... Thanks man
Maybe the double line formalism ?
I believe that they are a subclass of Feynman diagrams that do not show intermediate bosonic interactions; i.e. the relevant Feynman diagrams without any wiggly lines. The advantage is that any diagram with a continuous gap between the quarks is forbidden (suppressed) by Zweig's rule (iirc) and also that as flavour changing is relatively uncommon the lines often are just solid and 'simples'. Also, you don't have a whole infinity of gluons to worry about!
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