Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Duffin-Kemmer-Petiau and Klein-Gordon-Fock Equations for
  Electromagnetic, Yang-Mills and external Gravitational Field Interactions:
  proof of equivalence   Starting from Generating functional for Green Function (GF), constracted from
Lagrangian action in Duffin-Kemmer-Petiau (DKP) theory (L-approach) we strictly
prove that the physical matrix elements of S-matrix in DKP and
Klein-Gordon-Fock (KGF) theories coincide in cases of interaction spin O
particles with external and quantized Maxwell and Yang-Mills fields and in case
of external gravitational field (without or with torsion). For the proof we use
reduction formulas of Lehmann Symanzik, Zimmermann (LSZ). We prove that many
photons and Yang-Mills particles GF coincide in the both theories, too.

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The categories of this paper are: quant-ph
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The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
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The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
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The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: stat
1
The categories of this paper are: cs
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The categories of this paper are: supr-con
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The categories of this paper are: eess
2
The categories of this paper are: math