Surgery Obstructions on Closed Manifolds and the Inertia Subgroup
نویسنده
چکیده
The Wall surgery obstruction groups have two interesting geometrically defined subgroups, consisting of the surgery obstructions between closed manifolds, and the inertial elements. We show that the inertia group In+1(π,w) and the closed manifold subgroup Cn+1(π,w) are equal in dimensions n+1 ≥ 6, for any finitely-presented group π and any orientation character w : π → Z/2. This answers a question from [10, p. 107].
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