Hall’s Theorem for Limit Groups
نویسندگان
چکیده
منابع مشابه
Hall’s Theorem for limit groups
A celebrated theorem of Marshall Hall Jr. implies that finitely generated free groups are subgroup separable and that all of their finitely generated subgroups are retracts of finite-index subgroups. We use topological techniques inspired by the work of Stallings to prove that all limit groups share these two properties. This answers a question of Sela. Limit groups are finitely presented group...
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A celebrated theorem of Marshall Hall implies that finitely generated free groups are subgroup separable and that all of their finitely generated subgroups are retracts of finite-index subgroups. We use topological techniques inspired by the work of Stallings to prove that all limit groups share these two properties. This answers a question of Sela and provides a purely topological proof that f...
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ژورنال
عنوان ژورنال: Geometric and Functional Analysis
سال: 2008
ISSN: 1016-443X,1420-8970
DOI: 10.1007/s00039-008-0657-8