The singularity obstruction for group splittings
نویسنده
چکیده
We study an obstruction to splitting a finitely generated group G as an amalagamated free product or HNN extension over a given subgroup H and show that when the obstruction is “small” G splits over a related subgroup. Applications are given which generalise decomposition theorems from low dimensional topology.
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تاریخ انتشار 2004