The Kazhdan Property of the Mapping Class Group of Closed Surfaces and the First Cohomology Group of Its Cofinite Subgroups
نویسنده
چکیده
In the following we show that the mapping class group of a closed surface of genus 2 does not satisfy the Kazhdan property by constructing subgroups of nite index having a non-vanishing rst cohomology group. We also construct some subgroups of nite index in the mapping class group of a genus 3 surface and calculate their rst cohomology groups, which all turn out to be trivial. Most of the calculations have been carried out by the aid of a computer using the programming language GAP 1 (see [Sc]).
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ورودعنوان ژورنال:
- Experimental Mathematics
دوره 9 شماره
صفحات -
تاریخ انتشار 2000