A few remarks on intermediate subalgebras of an inclusion of C*-algebras

Keshab Chandra Bakshi; Satyajit Guin; Debabrata Jana

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arXiv · 2311.07244

A few remarks on intermediate subalgebras of an inclusion of C*-algebras

Keshab Chandra Bakshi·Satyajit Guin·Debabrata Jana

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Abstract

We show that the angle between intermediate $C^*$-subalgebras of an inclusion of simple $C^*$-algebras with finite Watatani index is stable. The notion of angle is instrumental in providing a bound for the cardinality of the lattice of intermediate subalgebras for an irreducible inclusion of simple $C^*$-algebras. We improve the existing upper bound for the cardinality of this set.

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Keshab Chandra Bakshi, Satyajit Guin, Debabrata Jana. 2023-11-13. A few remarks on intermediate subalgebras of an inclusion of C*-algebras. https://arxiv.org/abs/2311.07244

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