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Splittings of groups and intersection numbers

Peter Scott·Gadde A. Swarup
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Abstract

We prove algebraic analogues of the facts that a curve on a surface with self-intersection number zero is homotopic to a cover of a simple curve, and that two simple curves on a surface with intersection number zero can be isotoped to be disjoint.

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Peter Scott, Gadde A. Swarup. 2000-08-09. Splittings of groups and intersection numbers. https://doi.org/10.2140/gt.2000.4.179

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