On stable commutator length in hyperelliptic mapping class groups

Danny Calegari; Naoyuki Monden; Masatoshi Sato

doi:10.2140/pjm.2014.272.323

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arXiv · 1212.6117

On stable commutator length in hyperelliptic mapping class groups

Danny Calegari·Naoyuki Monden·Masatoshi Sato

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Abstract

We give a new upper bound on the stable commutator length of Dehn twists in hyperelliptic mapping class groups, and determine the stable commutator length of some elements. We also calculate values and the defects of homogeneous quasimorphisms derived from \omega-signatures, and show that they are linearly independent in the mapping class groups of pointed 2-spheres when the number of points is small.

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Danny Calegari, Naoyuki Monden, Masatoshi Sato. 2012-12-26. On stable commutator length in hyperelliptic mapping class groups. https://doi.org/10.2140/pjm.2014.272.323

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