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Somewhere trivial automorphisms

Saharon Shelah·Juris Steprāns
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Abstract

It is shown to be consistent that there is a non-trivial autohomeomorphism of beta N while all such autohomeomorphisms are trivial on some open set. The model used is one due to Velickovic in which, coincidentally, Martin's Axiom also holds.

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Saharon Shelah, Juris Steprāns. 1993-08-15. Somewhere trivial automorphisms. https://arxiv.org/abs/math/9308214

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