Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single particles and composite systems in a mathematically rigorous
  formulation of relativistic quantum field theory   We define quantum field theory by taking the Lagrangian action to be given as
a sequence of mathematically well-defined functionals written in terms of
operator fields fulfilling given \hbox{local} commutation relations. The
renormalized solution fields have a fully defined Fock space expansion and are
\hbox{multi-local}; thus Haag's theorem does not apply, i.e., the interaction
picture exists. Also, the formalism allows immediately the definition of a wave
function and the description of many-body bound-state systems.

13
The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg