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Groups with small Dehn functions and bipartite chord diagrams

Alexander Olshanskii·Mark Sapir
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Abstract

We introduce a new invariant of bipartite chord diagrams and use it to construct the first examples of groups with Dehn function $n^2\log n$ and other small Dehn functions. Some of these groups have undecidable conjugacy problem.

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Alexander Olshanskii, Mark Sapir. 2005-09-15. Groups with small Dehn functions and bipartite chord diagrams. https://arxiv.org/abs/math/0411174

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