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Two-Loop Computation of the Schroedinger Functional in Pure SU(3) Lattice Gauge Theory

A. Bode·P. Weisz·U. Wolff
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Abstract

We compute the Schroedinger functional (SF) for the case of pure SU(3) gauge theory at two-loop order in lattice perturbation theory. This allows us to extract the three-loop beta-function in the SF-scheme. These results are required to compute the running coupling, the Lambda-parameter and quark masses by finite size techniques with negligible systematic errors. In addition, we can now implement two-loop O(a) improvement in simulations and extend and study series in alternative ("tadpole-improved") bare couplings.

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A. Bode, P. Weisz, U. Wolff. 1998-09-25. Two-Loop Computation of the Schroedinger Functional in Pure SU(3) Lattice Gauge Theory. https://doi.org/10.1016/s0550-3213(98)00772-x

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