A note on semi-conjugacy for circle actions

Michelle Bucher; Roberto Frigerio; Tobias Hartnick

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arXiv · 1410.8350

A note on semi-conjugacy for circle actions

Michelle Bucher·Roberto Frigerio·Tobias Hartnick

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Abstract

We define a notion of semi-conjugacy between orientation-preserving actions of a group on the circle, which for fixed point free actions coincides with a classical definition of Ghys. We then show that two circle actions are semi-conjugate if and only if they have the same bounded Euler class. This settles some existing confusion present in the literature.

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BibTeX RIS

Michelle Bucher, Roberto Frigerio, Tobias Hartnick. 2014-10-30. A note on semi-conjugacy for circle actions. https://arxiv.org/abs/1410.8350

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