Proper morphisms and excellent schemes

Separated and Proper Morphisms

Last quarter, we introduced the closed diagonal condition for a prevariety to be a prevariety, and the “universally closed” condition for a variety to be complete. Earlier this quarter, we verified that in the case of complex prevarieties, these conditions are equivalent to the analytic topology being Hausdorff and compact, respectively. As we’ve discussed, in the scheme context a prevariety co...

Morphisms of Schemes

Étale Morphisms of Schemes

Contents 1. Introduction 1 2. Conventions 2 3. Unramified morphisms 2 4. Three other characterizations of unramified morphisms 4 5. The functorial characterization of unramified morphisms 5 6. Topological properties of unramified morphisms 6 7. Universally injective, unramified morphisms 7 8. Examples of unramified morphisms 9 9. Flat morphisms 10 10. Topological properties of flat morphisms 11...

Morphisms of Schemes

Morphisms of Schemes