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arXiv 0810.0043math.GR
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可达群的自同构群

The automorphism group of accessible groups

Mathieu Carette

摘要:

本文研究了群G的外自同构群,G分解为具有有限棱道群和至多一端的有限生成顶点群的有限图。我们证明了Out(G)本质上是由顶点群的相对自同构群、Dehn扭群和自由积的自同构群的扩张得到的。应用这一描述,我们得到了Out(G)可解的一个判据,以及Out(G)有限的一个充要条件.双曲群的后果进行了讨论。

英文摘要:

In this article, we study the outer automorphism group of a group G decomposed as a finite graph of group with finite edge groups and finitely generated vertex groups with at most one end. We show that Out(G) is essentially obtained by taking extensions of relative automorphism groups of vertex groups, groups of Dehn twists and groups of automorphisms of free products. We apply this description and obtain a criterion for Out(G) to be finitely presented, as well as a necessary and sufficient condition for Out(G) to be finite. Consequences for hyperbolic groups are discussed.

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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