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arXiv · 2211.10220

Decomposable Weak Expectations

Angshuman Bhattacharya·Chaitanya J. Kulkarni
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Abstract

In this article we define a special class of weak expectations for a representation of a separable unital C*-algebra, called decomposable weak expectation. We give necessary and sufficient conditions for such kind of weak expectations to exist for a given representation. Then we define decomposable measures on the state space of a C*-algebra and show that the GNS representation of a state admits a decomposable weak expectation if and only if there is a decomposable measure on the state space. Further we give an example of a decomposable weak expectation.

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Angshuman Bhattacharya, Chaitanya J. Kulkarni. 2022-11-18. Decomposable Weak Expectations. https://doi.org/10.4213/faa4351

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