Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Perturbative formulae for relativistic interactions of effective
  particles   The concept of effective particles as degrees of freedom in a relativistic
quantum field theory is defined using a non-perturbative renormalization group
procedure for Hamiltonians. However, every candidate for a basic physical
theory appears to require an initial perturbative search for the set of
interaction terms that may provide a basis with which the full effective theory
Hamiltonian could be constructed in a series of successive approximations. This
article describes the required perturbative expansion and illustrates it with a
set of general 4th-order formulae.

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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
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The categories of this paper are: acc-phys
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The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
2
The categories of this paper are: math
1
The categories of this paper are: cs
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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: stat
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The categories of this paper are: comp-gas
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The categories of this paper are: physics
33
The categories of this paper are: plasm-ph