Approximating L 2-Signatures by Their Compact Analogues
نویسندگان
چکیده
منابع مشابه
Approximating L-signatures by their compact analogues
Let Γ be a group together with a sequence of normal subgroups Γ ⊃ Γ1 ⊃ Γ2 ⊃ . . . of finite index [Γ : Γk] such that T k Γk = {1}. Let (X,Y ) be a (compact) 4n-dimensional Poincaré pair and p : (X,Y )→ (X,Y ) be a Γ-covering, i.e. normal covering with Γ as deck transformation group. We get associated Γ/Γk-coverings (Xk, Yk)→ (X,Y ). We prove that sign(X,Y ) = lim k→∞ sign(Xk, Yk) [Γ : Γk] , whe...
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ژورنال
عنوان ژورنال: Forum Mathematicum
سال: 2005
ISSN: 0933-7741,1435-5337
DOI: 10.1515/form.2005.17.1.31