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Infinite multiplicity of abelian subalgebras in free group subfactors

Marius Stefan
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Abstract

We obtain an estimate of Voiculescu's (modified) free entropy dimension for generators of a ${II}_1$-factor $\mc{M}$ with a subfactor $\mc{N}$ containing an abelian subalgebra $\mc{A}$ of finite multiplicity. It implies in particular that the interpolated free group subfactors of finite Jones index do not have abelian subalgebras of finite multiplicity or Cartan subalgebras.

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Marius Stefan. 2004-02-07. Infinite multiplicity of abelian subalgebras in free group subfactors. https://arxiv.org/abs/math/0402107

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