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arXiv · hep-th/9511041

The O(N) sigma-model Laplacian

Paul Mansfield·Jiannis Pachos
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Abstract

For fields that vary slowly on the scale of the lightest mass the logarithm of the vacuum functional of a massive quantum field theory can be expanded in terms of local functionals satisfying a form of the Schrödinger equation, the principal ingredient of which is a regulated functional Laplacian. We construct to leading order a Laplacian for the O(N) sigma-model that acts on such local functionals. It is determined by imposing rotational invariance in the internal space together with closure of the Poincaré algebra.

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Paul Mansfield, Jiannis Pachos. 1995-11-06. The O(N) sigma-model Laplacian. https://doi.org/10.1016/0370-2693(95)01333-4

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