Lemma 70.11.4. Let $X$ be an algebraic space over a perfect field $k$ (for example $k$ has characteristic zero).

1. For $x \in |X|$, if $\mathcal{O}_{X, \overline{x}}$ is reduced, then $X$ is geometrically reduced at $x$.

2. If $X$ is reduced, then $X$ is geometrically reduced over $k$.

Proof. The first statement follows from Algebra, Lemma 10.42.6 and the definition of a perfect field (Algebra, Definition 10.44.1). The second statement follows from the first. $\square$

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