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arXiv · 2211.07291

On possible values of the interior angle between intermediate subalgebras

Ved Prakash Gupta·Deepika Sharma
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Abstract

We show that all values in the interval $[0,\frac{\pi}{2}]$ can be attained as the interior angle between intermediate subalgebras (as introduced in [3]) of a certain inclusion of simple unital C*-algebras. We also calculate the interior angle between intermediate crossed product subalgebras of any inclusion of crossed product algebras corresponding to any action of a countable discrete group and its subgroups on a unital C*-algebra.

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Ved Prakash Gupta, Deepika Sharma. 2022-11-14. On possible values of the interior angle between intermediate subalgebras. https://doi.org/10.1017/s1446788723000058

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