Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Towards differential elimination of spinor field from spinor
  electrodynamics   A system of PDEs for the electromagnetic field and one real component of the
spinor field is generally equivalent to spinor electrodynamics. There are
reasons to believe that the component can be differentially eliminated from the
system. A Lagrangian depending on the electromagnetic field and one real
component of the spinor field generally describes the same physics as spinor
electrodynamics.

36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph