Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Some remarks on Dirac's hole theory versus quantum field theory   Dirac's hole theory and quantum field theory are generally considered to be
equivalent to each other. However, it has recently been shown that this is not
necessarily the case. In this article we will discuss the reason for this lack
of equivalence and suggest a possible solution.

12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph