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7 votes

properties of the fibers of a flat morphism

Hi, here are some references taken from Algebraic geometry I. Schemes. by Gortz and Wedhorn, Appendix E. These are generally scattered in EGAIV as far as I remember. Anyway, Kazuma Shimomoto recentl …
Karl Schwede's user avatar
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6 votes

Does smoothness descend along flat morphisms?

Here's a direct reference: Hochster Math 615 - 2004, February 18th It's a corollary of the characterization of regularity by the projective dimension of $R/m$. I found this by tracking references f …
Karl Schwede's user avatar
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5 votes

When can a finite map be blown up to a flat one?

Have you seen "Critères de platitude et de projectivité. Techniques de "platification'' d'un module" by Raynaud-Gruson (1971)? In particular 5.2.2. I think it is very close to what you want (this wa …
Karl Schwede's user avatar
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3 votes

When can one extend a flat family from a subscheme to the whole scheme?

This is not going to help too much in your case, but we do have the following I think. Suppose that we have a map $f : X \to Y$ which has a section (whose image we call $Y$ as well, as above), in oth …
Karl Schwede's user avatar
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