Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relative discrete spectrum of W*-dynamical systems   A definition of relative discrete spectrum of noncommutative W*-dynamical
systems is given in terms of the basic construction of von Neumann algebras,
motivated from three perspectives: Firstly, as a complementary concept to
relative weak mixing of W*-dynamical systems. Secondly, by comparison with the
classical (i.e. commutative) case. And, thirdly, by noncommutative examples.

18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg