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arXiv · 1903.07048

Comparing topologies on the Morse boundary and quasi-isometry invariance

Abstract

We compare several topologies on the Morse boundary $\partial_M Y$ of a $\mathrm{CAT(0)}$ cube complex $Y$. In particular, we show that the two topologies introduced by Cashen and Mackay are not equal in general and provide a new description of one of them in the language of cube complexes. As a corollary, we obtain a new approach to tackle the question whether the visual topology induces a quasi-isometry-invariant topology on the Morse boundary. This leads to an obstruction to quasi-isometry-invariance in terms of the behaviour of geodesics under quasi-isometries.

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BibTeXRIS

Merlin Incerti-Medici. 2019-03-17. Comparing topologies on the Morse boundary and quasi-isometry invariance. https://doi.org/10.1007/s10711-020-00553-3

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