Abstract commensurators of braid groups
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2007-05-23 v1 几何拓扑
摘要
Let B_n be the braid group on n strands, with n at least 4, and let Mod(S) be the extended mapping class group of the sphere with n+1 punctures. We show that the abstract commensurator of B_n is isomorphic to a semidirect product of Mod(S) with a group we refer to as the transvection subgroup, Tv(B_n). We also show that Tv(B_n) is itself isomorphic to a semidirect product of an infinite dimensional rational vector space with the multiplicative group of nonzero rational numbers.
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引用
@article{arxiv.math/0501480,
title = {Abstract commensurators of braid groups},
author = {Christopher J. Leininger and Dan Margalit},
journal= {arXiv preprint arXiv:math/0501480},
year = {2007}
}
备注
10 pages