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arXiv · 1310.2537

The Chillingworth Class is a Signed Stable Length

Ingrid Irmer
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Abstract

An orientation is defined on a family of curve graphs on which the Torelli group acts. It is shown that the resulting signed stable length of an element of the Torelli group is a cohomology class. This cohomology class is half the dual of the contraction of the Johnson homomorphism, the socalled "Chillingworth class".

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Ingrid Irmer. 2014-07-10. The Chillingworth Class is a Signed Stable Length. https://doi.org/10.2140/agt.2015.15.1863

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