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arXiv · 2109.09175

The boundary rigidity of lattices in products of trees

Kasia Jankiewicz·Annette Karrer·Kim Ruane·Bakul Sathaye
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Abstract

We show that every group acting freely and vertex-transitively by isometries on a product of two regular trees of finite valence is boundary rigid. That means that every CAT(0) space that admits a geometric action of any such group has the visual boundary homeomorphic to a join of two copies of the Cantor set.

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Kasia Jankiewicz, Annette Karrer, Kim Ruane, Bakul Sathaye. 2021-09-19. The boundary rigidity of lattices in products of trees. https://arxiv.org/abs/2109.09175

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