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arXiv · 0807.1994

A "typical" contraction is unitary

Tanja Eisner
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Abstract

We show that (for the weak operator topology) the set of unitary operators on a separable infinite-dimensional Hilbert space is residual in the set of all contractions. The analogous result holds for isometries and the strong operator topology as well. These results are applied to the problem of embedding operators into strongly continuous semigroups.

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Tanja Eisner. 2008-07-12. A "typical" contraction is unitary. https://arxiv.org/abs/0807.1994

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