Virtualities of Quarks and Gluons in Qcd Vacuum and Nonlocal Condensates within Single Instanton Approximation
نویسنده
چکیده
We calculate the lowest-dimensional nonlocal quark and gluon condensates within the single instanton approximation of the instanton liquid model. As a result, we determine the values of average virtualities of quarks λq and gluons λ 2 g in the QCD vacuum and obtain parameterless predictions for the ratio λg/λ 2 q = 12/5, and for some ratios of different vacuum condensates of higher dimensions. The nonlocal properties of quark and gluon condensates are analyzed, and insufficiency of the single instanton approximation is discussed.
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