Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Testing a CPT- and Lorentz-Violating Extension of the Standard Model   A brief summary is given of recent developments concerning a
Lorentz-violating extension of the standard model and its implications for
experiments testing Lorentz and CPT symmetry.

29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat