Approximately Multiplicative Decompositions of Nuclear Maps

Douglas A. Wagner

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arXiv · 2105.12250

Approximately Multiplicative Decompositions of Nuclear Maps

Douglas A. Wagner

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Abstract

We expand upon work from many hands on the decomposition of nuclear maps. Such maps can be characterized by their ability to be approximately written as the composition of maps to and from matrices. Under certain conditions (such as quasidiagonality), we can find a decomposition whose maps behave nicely, by preserving multiplication up to an arbitrary degree of accuracy and being constructed from order zero maps (as in the definition of nuclear dimension). We investigate these conditions and relate them to a W*-analog.

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Douglas A. Wagner. 2021-05-25. Approximately Multiplicative Decompositions of Nuclear Maps. https://arxiv.org/abs/2105.12250

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