Theory of bounded groups and their bounded cohomology
نویسندگان
چکیده
منابع مشابه
Bounded Cohomology Characterizes Hyperbolic Groups
A finitely presentable group G is hyperbolic if and only if the map H2 b (G, V ) → H2(G, V ) is surjective for any bounded G-module. The ‘only if’ direction is known and here we prove the ‘if’ direction. We also consider several ways to define a linear homological isoperimetric inequality.
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متن کاملBounded Cohomology and Non-uniform Perfection of Mapping Class Groups
Using the existence of certain symplectic submanifolds in symplectic 4-manifolds, we prove an estimate from above for the number of singular fibers with separating vanishing cycles in minimal Lefschetz fibrations over surfaces of positive genus. This estimate is then used to deduce that mapping class groups are not uniformly perfect, and that the map from their second bounded cohomology to ordi...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 1988
ISSN: 0030-8730,0030-8730
DOI: 10.2140/pjm.1988.134.313