Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A generally-relativistic gauge classification of the Dirac fields   We consider generally-relativistic gauge transformations for the spinorial
fields finding two mutually exclusive but together exhaustive classes in which
fermions are placed adding supplementary information to the results obtained by
Lounesto, and identifying quantities analogous to the momentum vector and the
Pauli-Lubanski axial vector we discuss how our results are similar to those
obtained by Wigner; by taking into account the system of Dirac field equations
we will investigate the consequences for the dynamics: and in particular we
shall address the problem of getting the non-relativistic approximation in a
consistent way. We are going to comment on extensions.

15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio