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The Laplacian subalgebra of the k-folded tensor product of the free group factor with itself is a strongly singular masa

Teodor Stefan Bildea
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Abstract

In this paper, we present a new class of strongly singular maximal abelian subalgebras living inside the k-folded tensor product of the free group factor (on N>1 generators). A. Sinclair and R. Smith introduced the class of strongly singular maximal abelian von Neumann algebras (MASA) of type II_1 factors. One of their examples was the Laplacian subalgebra of the free group factor, known to be a singularMASA. Using the techniques presented by A. Sinclair and R.Smith, we show that the Laplacian subalgebra of the k-folded tensor product of the free group factor with itself is a strongly singular MASA.

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Teodor Stefan Bildea. 2005-10-11. The Laplacian subalgebra of the k-folded tensor product of the free group factor with itself is a strongly singular masa. https://arxiv.org/abs/math/0503281

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