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arXiv · hep-lat/9509026

Running coupling constant and correlation length from Wilson loops

Massimo Campostrini·Paolo Rossi·Ettore Vicari
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Abstract

We consider a definition of the QCD running coupling constant $α(μ)$ related to Wilson loops of size $r{\times}t$ with arbitrary fixed $t/r$. The schemes defined by these couplings are very close to the $\overline{\rm MS}$ scheme for all values of $t/r$; in the $t/r\to\infty$ limit, the ``$q\bar q$ force'' scheme is recovered. We propose a definition of correlation length, also related to Wilson loops, which can be applied to the Monte Carlo evaluation of $α(μ)$ up to very large momentum scales by use of finite-size scaling techniques.

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Massimo Campostrini, Paolo Rossi, Ettore Vicari. 1995-09-12. Running coupling constant and correlation length from Wilson loops. https://doi.org/10.1016/0920-5632(96)00049-7

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