Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the absence and presence of pole(s) in fermion propagator in the
  simple model with mass generation   Within the Pauli-Villars regularization technique the fermion propagator is
studied in the framework of Schwinger-Dyson equations in the Euclidean space.
Making the generalization of Fukuda and Kugo proposals, the analytical
continuation is performed into the timelike region of fourmomenta. The massive
gauge boson kernel is considered and the fermion propagator pole structure is
discussed in detail.

9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th