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arXiv · 0906.1831

Conditional expectations onto maximal abelian *-subalgebras

Charles A. Akemann·David Sherman
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Abstract

We determine when there is a unique conditional expectation from a semifinite von Neumann algebra onto a singly-generated maximal abelian *-subalgebra. Our work extends the results of Kadison and Singer via new methods, notably the observation that a unique conditional expectation onto a singly-generated maximal abelian *-subalgebra must be normal.

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Charles A. Akemann, David Sherman. 2009-06-11. Conditional expectations onto maximal abelian *-subalgebras. https://arxiv.org/abs/0906.1831

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