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تسجيل مستخدم جديدNon-perturbative renormalization by decoupling
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We propose a new strategy for the determination of the QCD coupling. It relies on a coupling computed in QCD with $N_{rm f} geq 3$ degenerate heavy quarks at a low energy scale $mu_{rm dec}$, together with a non-perturbative determination of the ratio $Lambda/mu_{rm dec}$ in the pure gauge theory. We explore this idea using a finite volume renormalization scheme for the case of $N_{rm f} = 3$ QCD, demonstrating that a precise value of the strong coupling $alpha_s$ can be obtained. The idea is quite general and can be applied to solve other renormalization problems, using finite or infinite volume intermediate renormalization schemes.
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