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arXiv · hep-lat/9311019

Super-Instantons and the Reliability of Perturbation Theory in Non-Abelian Models

A. Patrascioiu·E. Seiler
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Abstract

In dimension $D\leq 2$ the low temperature behavior of systems enjoying a continuous symmetry is dominated by super-instantons: classical configurations of arbitrarily low energy. Perturbation theory in the background of a super-instanton produces thermodynamic answers for the invariant Green's functions that differ from the standard ones, but only in non-Abelian models and only starting at $O(1/β^2)$. This effect modifies the $β$-function of the $O(N)$ models and persists in the large $N$ limit of the $O(N)$ models.

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A. Patrascioiu, E. Seiler. 1993-11-18. Super-Instantons and the Reliability of Perturbation Theory in Non-Abelian Models. https://doi.org/10.1103/physrevlett.74.1920

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