Abstract
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: First, as a complementary concept to relative weak mixing of W*-dynamical systems. Second, by comparison with the classical (i.e., commutative) case. And, third, by noncommutative examples.
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We thank the referee for suggestions to improve the exposition. This work was partially supported by the National Research Foundation of South Africa.
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Communicated by Fedor Sukochev.
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Duvenhage, R., King, M. Relative discrete spectrum of W*-dynamical system. Banach J. Math. Anal. 15, 2 (2021). https://doi.org/10.1007/s43037-020-00089-4
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DOI: https://doi.org/10.1007/s43037-020-00089-4