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arXiv · 2102.01462

A few remarks on Pimsner-Popa bases and regular subfactors of depth 2

Keshab Chandra Bakshi·Ved Prakash Gupta
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Abstract

We prove that a finite index regular inclusion of $II_1$-factors with commutative first relative commutant is always a crossed product subfactor with respect to a minimal action of a biconnected weak Kac algebra. Prior to this, we prove that every finite index inclusion of $II_1$-factors which is of depth $2$ and has simple first relative commutant (respectively, is regular and has commutative or simple first relative commutant) admits a two-sided Pimsner-Popa basis (respectively, a unitary orthonormal basis)

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Keshab Chandra Bakshi, Ved Prakash Gupta. 2021-02-02. A few remarks on Pimsner-Popa bases and regular subfactors of depth 2. https://doi.org/10.1017/s0017089521000379

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