ΛMS from renormalization group optimized perturbation
نویسندگان
چکیده
A variationally optimized perturbation, combined with renormalization group properties, can give approximations to certain nonperturbative quantities like the chiral symmetry breaking order parameters. We evaluate, up to third order in this modified perturbation, F π /Λ MS , where F π is the pion decay constant and Λ MS the basic QCD scale in the MS scheme. We obtain Λ
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