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Completion of ring as direct limit

Let $A$ be a local ring with maximal ideal $\frak{m}$ and let $\hat{A}$ be its completion with respect to $\mathfrak{m}$.

Suppose that the map $A \rightarrow \hat{A}$ is regular (apparently this is the case if $A$ is an excellent local ring). By Popescu's theorem $\hat{A}$ is a direct limit of smooth (finitely presented) $A$-algebras.

I would like to know if $\hat{A}$ is actually a direct limit of étale $A$-algebras or if there is another characterisation of such maps.

To put the result into context, the henselisation $A^h$ of $A$ is obtained as a direct limit of étale $A$-algebras with a distinguished point and prescribed residue field.

ofiz
  • 635
  • 4
  • 10