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arXiv · hep-lat/9607061

Classical improvement of lattice actions and quantum effects: a unified view

Paolo Rossi·Ettore Vicari
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Abstract

The possibility of removing the one-loop perturbative effects of lattice artifacts by a proper choice of the lattice action is explored, and found to depend crucially on the properties of the physical quantity considered. In this respect the finite-space-volume mass gap m(L) is an improved observable. We find an explicit momentum space representation of the one-loop contribution to m(L) for arbitrary lattice actions in the case of two-dimensional O(N) sigma models. We define a ``tree perfect'' Symanzik action and find that it formally removes all one-loop lattice artifacts in m(L). On-shell improved actions do not share this property.

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Paolo Rossi, Ettore Vicari. 1996-07-26. Classical improvement of lattice actions and quantum effects: a unified view. https://doi.org/10.1016/s0370-2693(96)01320-2

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