Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Approximately transitive dynamical systems and simple spectrum   For some countable discrete torsion Abelian groups we give examples of their
finite measure-preserving actions which have simple spectrum and no approximate
transitivity property.

24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex