Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: One loop beta functions and fixed points in Higher Derivative Sigma
  Models   We calculate the one loop beta functions for nonlinear sigma models in four
dimensions containing general two and four derivative terms. In the O(N) model
there are four such terms and nontrivial fixed points exist for all N \geq 4.
In the chiral SU(N) models there are in general six couplings, but only five
for N=3 and four for N=2; we find fixed points only for N=2,3. In the
approximation considered, the four derivative couplings are asymptotically free
but the coupling in the two derivative term has a nonzero limit. These results
support the hypothesis that certain sigma models may be asymptotically safe.

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The categories of this paper are: atom-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: chao-dyn
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The categories of this paper are: mtrl-th
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The categories of this paper are: math
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The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
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The categories of this paper are: comp-gas
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: cond-mat