Fancy and facts in the (d - 2) expansion of non-linear sigma models

E. Brezin; S. Hikami

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arXiv · cond-mat/9612016

Fancy and facts in the (d - 2) expansion of non-linear sigma models

E. Brezin·S. Hikami

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Abstract

We review the existing results on the scaling dimensions of operators with more than two derivatives in the non-linear sigma models. We argue that the speculations on the relevance of these operators, and correspondingly on the breakdown of the $(d-2)$ expansion for the classical Heisenberg model, or for the one-parameter scaling theory of localization, are based on a dubious mathematical analysis.

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E. Brezin, S. Hikami. 1996-12-02. Fancy and facts in the (d - 2) expansion of non-linear sigma models. https://arxiv.org/abs/cond-mat/9612016

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