Is there a proof for Proposition 2.1.4 of Local Cohomology book by Brodmann-Sharp not using Artin–Rees Lemma?
Proposition 2.1.4: Let $I$ be an injective $R$-module. Then $\Gamma_{\mathfrak a}(I)$ is also an injective $R$-module.
Is there a proof for Proposition 2.1.4 of Local Cohomology book by Brodmann-Sharp not using Artin–Rees Lemma?
Proposition 2.1.4: Let $I$ be an injective $R$-module. Then $\Gamma_{\mathfrak a}(I)$ is also an injective $R$-module.
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There is one at exercise 10.1.11 of the book, which I gave a proof (not in details):
$I= \oplus E(R/\mathfrak p)$ being injective we have that $$\Gamma_{\mathfrak a}(I) = \Gamma_{\mathfrak a}({\oplus E(R/\mathfrak p)} )= \oplus \Gamma_{\mathfrak a}({E(R/\mathfrak p)})=\oplus_{\mathfrak a\subseteq \mathfrak p} E(R/\mathfrak p)$$ is injective, since $R$ is noetherian (see Theorem 18.4 of Matsumura's Commutative Ring Theory).