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On certain automorphisms of sets of partial isometries

Lajos Molnar
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Abstract

Under the mild condition of continuity at a single point we describe all the bijections of the set of all partial isometries on a Hilbert space which preserve the order and the orthogonality in both directions. Moreover, we present a natural analogue of Wigner's theorem on quantum mechanical symmetries for the set of all rank-1 partial isometries.

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Lajos Molnar. 2000-11-04. On certain automorphisms of sets of partial isometries. https://arxiv.org/abs/math/0011028

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