arXiv math/04010422004-01-20math.GR

Limit groups as limits of free groups: compactifying the set of free groups

Christophe Champetier, Vincent Guirardel

备注：: Decembre 2003. 57 pages. (Correction d'une imprecision)
发表信息：: Israël Journal of Mathematics 146 (2005) 1

英文摘要：

We give a topological framework for the study of Sela's limit groups: limit groups are limits of free groups in a compact space of marked groups. Many results get a natural interpretation in this setting. The class of limit groups is known to coincide with the class of finitely generated fully residually free groups. The topological approach gives some new insight on the relation between fully residually free groups, the universal theory of free groups, ultraproducts and non-standard free groups.

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