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arXiv · 2605.29125

When is the Ellis semigroup a complete conjugacy invariant?

Johannes Kellendonk·Reem Yassawi
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Abstract

The Ellis semigroup of a topological dynamical system contains algebraic, topological and dynamical information. It is invariant under conjugacy. Despite this wealth of structure, two non-conjugate dynamical systems can have the same Ellis semigroup. We identify a class of minimal dynamical systems inside which this cannot happen, that is, for which the Ellis semigroup is a complete conjugacy invariant.

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Johannes Kellendonk, Reem Yassawi. 2026-05-27. When is the Ellis semigroup a complete conjugacy invariant?. https://arxiv.org/abs/2605.29125

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