High-gradient operators in the N-vector model

S. E. Derkachov; S. K. Kehrein; A. N. Manashov

doi:10.1016/s0550-3213(97)00131-4

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arXiv · cond-mat/9610106

High-gradient operators in the N-vector model

S. E. Derkachov·S. K. Kehrein·A. N. Manashov

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Abstract

It has been shown by several authors that a certain class of composite operators with many fields and gradients endangers the stability of nontrivial fixed points in 2+eps expansions for various models. This problem is so far unresolved. We investigate it in the N-vector model in an 1/N-expansion. By establishing an asymptotic naive addition law for anomalous dimensions we demonstrate that the first orders in the 2+eps expansion can lead to erroneous interpretations for high--gradient operators. While this makes us cautious against over--interpreting such expansions (either 2+eps or 1/N), the stability problem in the N-vector model persists also in first order in 1/N below three dimensions.

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BibTeX RIS

S. E. Derkachov, S. K. Kehrein, A. N. Manashov. 1996-11-07. High-gradient operators in the N-vector model. https://doi.org/10.1016/s0550-3213(97)00131-4

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