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Algebraic Topology · Problem 34
Cohomology — Allen Hatcher
Mathematics — Topology · poincare-duality-boundary-diagram
Problem For a compact manifold M M M verify that the following diagram relating Poincar\'e duality for M M M and ∂ M \partial M ∂ M is commutative, up to sign at least:
H k − 1 ( ∂ M ; R ) ⟶ H k ( M , ∂ M ; R ) ⟶ H k ( M ; R ) ⟶ H k ( ∂ M ; R ) ↓ [ ∂ M ] ⌢ ↓ [ M ] ⌢ ↓ [ M ] ⌢ ↓ [ ∂ M ] ⌢ H n − k ( ∂ M ; R ) ⟶ H n − k ( M ; R ) ⟶ H n − k ( M , ∂ M ; R ) ⟶ H n − k − 1 ( ∂ M ; R ) \begin{array}{ccccccc}
H^{k-1}(\partial M; R) & \longrightarrow & H^k(M, \partial M; R) & \longrightarrow & H^k(M; R) & \longrightarrow & H^k(\partial M; R) \\
\downarrow [\partial M] \frown & & \downarrow [M] \frown & & \downarrow [M] \frown & & \downarrow [\partial M] \frown \\
H_{n-k}(\partial M; R) & \longrightarrow & H_{n-k}(M; R) & \longrightarrow & H_{n-k}(M, \partial M; R) & \longrightarrow & H_{n-k-1}(\partial M; R)
\end{array} H k − 1 ( ∂ M ; R ) ↓ [ ∂ M ] ⌢ H n − k ( ∂ M ; R ) ⟶ ⟶ H k ( M , ∂ M ; R ) ↓ [ M ] ⌢ H n − k ( M ; R ) ⟶ ⟶ H k ( M ; R ) ↓ [ M ] ⌢ H n − k ( M , ∂ M ; R ) ⟶ ⟶ H k ( ∂ M ; R ) ↓ [ ∂ M ] ⌢ H n − k − 1 ( ∂ M ; R )
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