Path Dependence of the Quark Nonlocal Condensate within the Instanton Model
نویسندگان
چکیده
The nonlocal vacuum condensates or vacuum correlators describe the distribution of quarks and gluons in the nonperturbative QCD vacuum [1]. Physically, it means that vacuum quarks and gluons can flow through the vacuum with nonzero momentum. Nonlocal condensates play an important role in hadron physics. The nonlocal properties of the vacuum condensates are of principle importance in the study of the distribution functions of quarks and gluons in QCD vacuum and in hadrons [1, 2]. In general, the gauge–invariant (and path independent) nonlocal quark-quark correlator is defined by
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ar X iv : h ep - p h / 04 05 29 3 v 1 29 M ay 2 00 4 Path Dependence of the Quark Nonlocal Condensate within the Instanton Model
The nonlocal vacuum condensates or vacuum correlators describe the distribution of quarks and gluons in the non-perturbative QCD vacuum [1]. Physically, it means that vacuum quarks and gluons can flow through the vacuum with nonzero momentum. Nonlocal condensates play an important role in hadron physics. In particular, they are of principle importance in the study of the distribution functions ...
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