bio | website | perso.univ-rennes1.fr/… |
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location | Rennes | |
age | 38 | |
visits | member for | 4 years, 6 months |
seen | 3 hours ago | |
stats | profile views | 680 |
Nov 16 |
revised |
Is this formally étale morphism of schemes an isomorphism?
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Nov 15 |
revised |
Is this formally étale morphism of schemes an isomorphism?
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Nov 15 |
answered | Is this formally étale morphism of schemes an isomorphism? |
Nov 8 |
comment |
Is this formally étale morphism of schemes an isomorphism?
Two questions: 1) I'd be happy to have details on the proof that $\mathfrak{m}'=\mathfrak{m}B$. 2) For formal glueing in the very last step, the quoted lemma from the Stacks Project requires to know that $B$ is a finite $A$-module, how do you deal with this issue? |
Nov 4 |
comment |
Fantastic properties of Z/2Z
That is terrific! Do you know a reference where I can read more on this? |
Nov 3 |
accepted | Is this formally étale morphism of schemes an isomorphism? |
Nov 3 |
comment |
Is this formally étale morphism of schemes an isomorphism?
OK, I get it. Thank you for this nice contribution. The particular situation that I have in mind has additional features (like quasicompactness) that your example doesn't, but it helped me anyway to understand things better. Thanks again! (And if you happen to have ideas in the quasicompact case...) |
Nov 3 |
revised |
Is this formally étale morphism of schemes an isomorphism?
Added assumptions to the original question to fit with the actual situation I'm interested in. |
Nov 3 |
comment |
Is this formally étale morphism of schemes an isomorphism?
Why it is true that $f$ is an iso on local rings at points of $Y$? |
Nov 3 |
comment |
Is this formally étale morphism of schemes an isomorphism?
... and $S$ is noetherian. |
Nov 3 |
comment |
Is this formally étale morphism of schemes an isomorphism?
In view of the example given by user52824 below, I wish to emphasize my comment 1: I am in fact interested in the case where $f$ is quasicompact. |
Nov 2 |
asked | Is this formally étale morphism of schemes an isomorphism? |
Nov 2 |
awarded | Notable Question |
Nov 2 |
awarded | Good Question |
Oct 17 |
answered | Wonderful applications of the Vandermonde determinant |
Oct 13 |
comment |
The quotient stack $[\mathbb{A}^n / \mathrm{GL}_n]$
@André, Ben: you're perfectly right of course. |
Oct 12 |
comment |
The quotient stack $[\mathbb{A}^n / \mathrm{GL}_n]$
This stack classifies vector bundles of rank $n$ together with $n$ global sections. You see it just like you see that $A^1/G_m$ classifies line bundles with a global section. |
Sep 23 |
comment |
Is every module the colimit of its finitely generated submodules? (for algebraic spaces or stacks)
David Rydh eventually removed the assumptions on the diagonal, see arxiv.org/abs/1408.6698. |
Sep 3 |
comment |
Existence of affine hulls
... by Matthieu Romagny's wrong answer to... |
Aug 29 |
revised |
Affine hulls and base change
added 95 characters in body |