nLab
étale algebra

Context

Étale morphisms

étale morphism (submersion, immersion)

generally in differential cohesion

in topology

in differential geometry

in algebraic geometry

Geometry

Contents

Definition

An RR-algebra AA is étale if the definition homomorphism RAR \to A is, dually, an étale morphism of schemes.

A more elementary definition for algebras over a discrete field exists in constructive algebra.

étale morphism\Rightarrow pro-étale morphism \Rightarrow weakly étale morphism \Rightarrow formally étale morphism

References

Henri Lombardi & Claude Quitté, Constructive Algebra, Constructive Methods, 2014, PDF

Last revised on May 21, 2014 at 03:41:09. See the history of this page for a list of all contributions to it.