Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic field equations from higher-order polarizations of the
  Poincar\'e group   The theory of free relativistic fields is shown to arise in a unified manner
from higher-order, configuration-space, irreducible representations of the
Poincar\'e group. A de Sitter subalgebra, in the massive case, and a Poincar\'e
subalgebra, in the massless case, of the enveloping algebra of the Poincar\'e
group are the suitable higher-order polarizations. In particular, a simple
group-theoretic derivation of the Dirac equation is given.

30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat