Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamical Chiral Symmetry Breaking from Variationally Improved
  Perturbative Expansion   We review how a specific resummation of the so-called "delta-expansion",
applied to the QCD Lagrangian, transforms the ordinary perturbative expansion
in $\alpha_s$ into an expansion in an arbitrary mass parameter, around the
basic scale $\bar\Lambda$. When applied to the pole mass, the resulting
expression may be interpreted as a dynamical mass ansatz, to be optimized with
respect to the new expansion (mass) parameter. The construction is generalized
to obtain estimates of the order parameters of the $SU(n_f)_L \times SU(n_f)_R$
($n_f =2,3$) symmetry breakdown.

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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: plasm-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: math
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: cond-mat
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The categories of this paper are: supr-con