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The absence of cut--off effects for the fixed point action in 1--loop perturbation theory

F. Farchioni·P. Hasenfratz·F. Niedermayer·A. Papa
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Abstract

In order to support the formal renormalization group arguments that the fixed point action of an asymptotically free model gives cut--off independent physical predictions in 1--loop perturbation theory, we calculate the finite volume mass--gap $m(L)$ in the non--linear $σ$--model. No cut--off effect of the type $g^4\left(a/L\right)^n$ is seen for any $n$. The results are compared with those of the standard and tree level improved Symanzik actions.

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F. Farchioni, P. Hasenfratz, F. Niedermayer, A. Papa. 1995-06-28. The absence of cut--off effects for the fixed point action in 1--loop perturbation theory. https://doi.org/10.1016/0550-3213(95)00460-a

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