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arXiv · 2503.16722

Cleanliness versus Specialness

Kasia Jankiewicz
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Abstract

We show that the fundamental group of a geometrically clean graph of finite rank free groups does not need to be virtually compact special, answering a question of Wise. This implies that the class of the virtually VH-clean graphs of finite rank free groups is a proper subclass of the class of virtually geometrically clean graphs of finite rank free groups.

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Kasia Jankiewicz. 2025-03-20. Cleanliness versus Specialness. https://arxiv.org/abs/2503.16722

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