arXiv 0811.08412008-11-05math.GTmath.GR

Injections of mapping class groups

Javier Aramayona, Christopher J. Leininger, Juan Souto

发表信息：: Geom. Topol. 13 (2009) 2523-2541
DOI：: 10.2140/gt.2009.13.2523

英文摘要：

We construct new monomorphisms between mapping class groups of surfaces. The first family of examples injects the mapping class group of a closed surface into that of a different closed surface. The second family of examples are defined on mapping class groups of once-punctured surfaces and have quite curious behaviour. For instance, some pseudo-Anosov elements are mapped to multi-twists. Neither of these two types of phenomena were previously known to be possible although the constructions are elementary.

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