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arXiv · 1507.00135

Sigma 1 of PL-homeomorphism groups

Ralph Strebel
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Abstract

I survey the known results about the invariant Sigma 1 of groups of PL-homeomorphisms of a compact interval and supplement them with new results about Sigma 1 of PL-homeomorphism groups of a half line or a line. The proofs are based on the Cayley-graph definition of the invariant.

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Ralph Strebel. 2015-07-01. Sigma 1 of PL-homeomorphism groups. https://arxiv.org/abs/1507.00135

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