Bourbaki

Corollary

Tag 0DCZ, permanent. Cite it as [Bourbaki, Tag 0DCZ].

Commutative Algebra, chapter X, § 10. Cohomologie locale, dualité de Grothendieck

The homomorphism D(ω):Ω^→D(HAd(A))D(\omega) : \widehat{\Omega} \to D(H^d_A(A)) is an isomorphism.

Let MM be an AA-module, and ii an integer. Consider the canonical homomorphisms (§ 8, No. 7)

ρd−i(M,Ω):Tord−iA(M,D(Ω))⟶D(ExtAd−i(M,Ω)) \rho_{d-i}(M, \Omega) : \mathrm{Tor}^A_{d-i}(M, D(\Omega)) \longrightarrow D(\mathrm{Ext}_A^{d-i}(M, \Omega))
θd−i(M,HAd(A)):ExtAd−i(M,D(HAd(A)))⟶D(Tord−iA(M,HAd(A))). \theta^{d-i}(M, H^d_A(A)) : \mathrm{Ext}_A^{d-i}(M, D(H^d_A(A))) \longrightarrow D(\mathrm{Tor}^A_{d-i}(M, H^d_A(A))) .

With the aid of the isomorphisms ω:HAd(A)→D(Ω)\omega : H^d_A(A) \to D(\Omega), D(ω):Ω^→D(HAd(A))D(\omega) : \widehat{\Omega} \to D(H^d_A(A)) (cor. 1 of prop. 2) and τi(M):Tord−iA(M,HAd(A))→HAi(M)\tau^i(M) : \mathrm{Tor}^A_{d-i}(M, H^d_A(A)) \to H^i_A(M) (No. 2), one deduces from them canonical homomorphisms of AA-modules

γi(M):HAi(M)⟶D(ExtAd−i(M,Ω)) \gamma^i(M) : H^i_A(M) \longrightarrow D(\mathrm{Ext}_A^{d-i}(M, \Omega))
δi(M):ExtAd−i(M,Ω^)⟶D(HAi(M)). \delta^i(M) : \mathrm{Ext}_A^{d-i}(M, \widehat{\Omega}) \longrightarrow D(H^i_A(M)) .

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

Nothing.

Translated with machine help, not yet reviewed by a person.