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arXiv · hep-lat/9411018

Two-loop computation of a finite volume running coupling on the lattice

Ulli Wolff
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Abstract

In pure SU(2) gauge theory we compute the two-loop coefficient in the relation between the lattice bare coupling and the running coupling defined through the Schroedinger functional. This result is required to relate the latter to the MSbar-coupling in our programme to compute alpha_s. In addition it allows us to implement O(a) improvement of the Schroedinger functional to two-loop order. The two-loop beta-function is verified in a perturbative computation on the lattice, and the behavior of expansions in the standard and in the Parisi-improved bare couplings are investigated beyond one loop.

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Ulli Wolff. 1995-01-17. Two-loop computation of a finite volume running coupling on the lattice. https://doi.org/10.1016/0920-5632(95)00230-7

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