Commensurating HNN extensions: nonpositive curvature and biautomaticity
نویسندگان
چکیده
We show that the commensurator of any quasiconvex abelian subgroup in a biautomatic group is small, sense it has finite image abstract subgroup. Using this criterion we exhibit groups are CAT(0) but not biautomatic. These also resolve number other questions concerning groups.
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ژورنال
عنوان ژورنال: Geometry & Topology
سال: 2021
ISSN: ['1364-0380', '1465-3060']
DOI: https://doi.org/10.2140/gt.2021.25.1819