Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Notes on The Feynman Checkerboard Problem   The Feynman checkerboard problem is an interesting path integral approach to
the Dirac equation in `1+1' dimensions. I compare two approaches reported in
the literature and show how they may be reconciled. Some physical insights may
be gleaned from this approach.

23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex