The Stacks project

Lemma 31.12.4. Let $X$ be an integral locally Noetherian scheme. Let $\mathcal{F}$ be a coherent $\mathcal{O}_ X$-module.

  1. If $\mathcal{F}$ is reflexive, then $\mathcal{F}$ is torsion free.

  2. The map $j : \mathcal{F} \longrightarrow \mathcal{F}^{**}$ is injective if and only if $\mathcal{F}$ is torsion free

Proof. Omitted. See More on Algebra, Lemma 15.23.2. $\square$


Comments (1)

Comment #6273 by Matthieu Romagny on

Add a point at the end of condition (2).


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