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arXiv 1001.3587math.GRmath.GT
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直角Artin群的发散与拟同构

Divergence and quasimorphisms of right-angled Artin groups

Jason Behrstock, Ruth Charney

摘要:

给出了定义图G为连通的直角Artin群A(G)的Cayley图中具有超线性发散的测地线的群论刻画。我们利用这一点来确定A(G)的一个渐近锥面中的两点何时被一个截点分开。作为应用,我们证明了如果G不分解为两个子图的并,则A(G)有一个无限维的非平凡拟同构空间。通过伯格和莫诺的工作,这导致了从格到直角阿廷群的同态的超刚性定理。

英文摘要:

We give a group theoretic characterization of geodesics with superlinear divergence in the Cayley graph of a right-angled Artin group A(G) with connected defining graph G. We use this to determine when two points in an asymptotic cone of A(G) are separated by a cut-point. As an application, we show that if G does not decompose as the join of two subgraphs, then A(G) has an infinite-dimensional space of non-trivial quasimorphisms. By the work of Burger and Monod, this leads to a superrigidity theorem for homomorphisms from lattices into right-angled Artin groups.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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