Quasi-homomorphisms on mapping class groups
نویسندگان
چکیده
منابع مشابه
Quasi-homomorphisms on Mapping Class Groups
We refine the construction of quasi-homomorphisms on mapping class groups. It is useful to know that there are unbounded quasihomomorphisms which are bounded when restricted to particular subgroups since then one deduces that the mapping class group is not boundedly generated by these subgroups. In this note we enlarge the class of such subgroups. The generalization is motivated by consideratio...
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This is an addendum to [BDS]. We show, using our methods and an auxiliary result of Bestvina-Bromberg-Fujiwara, that a finitely generated group with infinitely many pairwise non-conjugate homomorphisms to a mapping class group virtually acts non-trivially on an R-tree, and, if it is finitely presented, it virtually acts non-trivially on a simplicial tree. The goal of this addendum to [BDS] is t...
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ژورنال
عنوان ژورنال: Glasnik Matematicki
سال: 2007
ISSN: 0017-095X
DOI: 10.3336/gm.42.1.15