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Some multiplicative preservers on $BH)$

Lajos Molnar
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Abstract

In this paper we describe the form of those continuous multiplicative maps on B(H) (H being a separable complex Hilbert space of dimension not less than 3) which preserve the rank, or the corank. Furthermore, we characterize those continuous *-semigroup endomorphisms of B(H) which are spectrum non-increasing.

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Lajos Molnar. 1999-09-09. Some multiplicative preservers on $BH)$. https://arxiv.org/abs/math/9909048

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