Gauge–invariant nonlocal quark condensates in QCD: a new interpretation of the lattice results

نویسنده

  • E. Meggiolaro
چکیده

where S(0, x) is the Schwinger line needed to make Ci(x) gauge–invariant and Γ are the sixteen independent matrices of the Clifford’s algebra acting on the Dirac indices a, b. The trace in (1) is taken with respect to the colour indices. Making use of T,P invariance one can prove that all the correlators (1) vanish, except those with Γ = 1 (“scalar” nonlocal condensate) and with Γ = γ E and μ in the direction of x (“longitudinal–vector” nonlocal condensate):

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تاریخ انتشار 1999