Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Introduction to Chiral Perturbation Theory   This article provides a pedagogical introduction to the basic concepts of
chiral perturbation theory and is designed as a text for a two-semester course
on that topic.
  Chapter 1 serves as a general introduction to the empirical and theoretical
foundations which led to the development of chiral perturbation theory.
  Chapter 2 deals with QCD and its global symmetries in the chiral limit; the
concept of Green functions and Ward identities reflecting the underlying chiral
symmetry is elaborated.
  In Chap. 3 the idea of a spontaneous breakdown of a global symmetry is
discussed and its consequences in terms of the Goldstone theorem are
demonstrated.
  Chapter 4 deals with mesonic chiral perturbation theory and the principles
entering the construction of the chiral Lagrangian are outlined.
  Various examples with increasing chiral orders and complexity are given.
  Finally, in Chap. 5 the methods are extended to include the interaction
between Goldstone bosons and baryons in the single-baryon sector, with the main
emphasis put on the heavy-baryon formulation.
  At the end, the method of infrared regularization in the relativistic
framework is discussed.

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The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
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The categories of this paper are: mtrl-th
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The categories of this paper are: ao-sci
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The categories of this paper are: adap-org
3
The categories of this paper are: physics
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The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: econ