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arXiv · 1906.05493

Arveson's characterisation of CCR flows: the multiparameter case

S. Sundar
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Abstract

In this paper, we revisit Arveson's characterisation of CCR flows in terms of decomposibility of the product system in the multiparameter context. We show that a multiparameter $E_0$-semigroup is a CCR flow if and only if it is decomposable and admits a unit. In contrast to the one parameter situtation, we exhibit uncountably many examples of decomposable $E_0$-semigroups which do not admit any unit. As applications, we show that for a pure isometric representation $V$, the associated CCR flow $\alpha^{V}$ remembers the unitary equivalence class of $V$. We also compute the positive contractive local cocycles and projective local cocycles of a CCR flow. A necessary and a sufficient condition for a CCR flow to be prime is obtained.

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S. Sundar. 2019-06-13. Arveson's characterisation of CCR flows: the multiparameter case. https://arxiv.org/abs/1906.05493

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