Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A possibility of CPT violation in the Standard Model   It is shown that there is a possibility of violation of CPT symmetry in the
Standard Model which does not contradict to the famous CPT theorem. To check
this possibility experimentally it is necessary to increase the precision of
measurements of the proton and antiproton mass difference by an order of
magnitude

13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org