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arXiv · 2605.01795

Factors with prescribed number of invariant subalgebras not arising from subgroups

Yongle Jiang·Qinxuan Xu
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Abstract

For any given integer $n\geq 1$, we construct i.c.c. groups $G$ such that the II$_1$ factors $L(G)$ have exactly $n$-many $G$-invariant von Neumann subalgebras not arising from subgroups.

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Yongle Jiang, Qinxuan Xu. 2026-05-03. Factors with prescribed number of invariant subalgebras not arising from subgroups. https://arxiv.org/abs/2605.01795

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