Non-planar ends are continuously unforgettable

Javier Aramayona; Rodrigo De Pool; Rachel Skipper; Jing Tao; Nicholas G. Vlamis; Xiaolei Wu

doi:10.1093/imrn/rnaf026

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arXiv · 2409.05502

Non-planar ends are continuously unforgettable

Javier Aramayona·Rodrigo De Pool·Rachel Skipper·Jing Tao·Nicholas G. Vlamis·Xiaolei Wu

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Abstract

We show that continuous epimorphisms between a class of subgroups of mapping class groups of orientable infinite-genus 2-manifolds with no planar ends are always induced by homeomorphisms. This class of subgroups includes the pure mapping class group, the closure of the compactly supported mapping classes, and the full mapping class group in the case that the underlying manifold has a finite number of ends or is perfectly self-similar. As a corollary, these groups are Hopfian topological groups.

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Javier Aramayona, Rodrigo De Pool, Rachel Skipper, Jing Tao, Nicholas G. Vlamis, Xiaolei Wu. 2024-09-09. Non-planar ends are continuously unforgettable. https://doi.org/10.1093/imrn%2Frnaf026

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