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arXiv · 1808.03181

Optimal transport and unitary orbits in C*-algebras

Bhishan Jacelon·Karen R. Strung·Alessandro Vignati
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Abstract

Two areas of mathematics which have received substantial attention in recent years are the theory of optimal transport and the Elliott classification programme for C*-algebras. We combine these two seemingly unrelated disciplines to make progress on a classical problem of Weyl. In particular, we show how results from the Elliott classification programme can be used to translate continuous transport of spectral measures into optimal unitary conjugation in C*-algebras. As a consequence, whenever two normal elements of a sufficiently well-behaved C*-algebra share a spectrum amenable to such continuous transport, and have trivial K_1-class, the distance between their unitary orbits can be computed tracially.

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Bhishan Jacelon, Karen R. Strung, Alessandro Vignati. 2018-08-09. Optimal transport and unitary orbits in C*-algebras. https://arxiv.org/abs/1808.03181

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