Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on Cherenkov radiation in magnetized vacuum   The Cherenkov radiation in the vacuum with constant magnetic background is
denied within quantum kinematics in spite of the refractive index of that
equivalent medium being greater than unity.

13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an