bio | website | math.u-bordeaux1.fr/~qliu |
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location | Bordeaux | |
age | ||
visits | member for | 4 years, 2 months |
seen | Nov 9 '13 at 19:47 | |
stats | profile views | 4,372 |
Jan 23 |
awarded | Yearling |
Dec 3 |
awarded | Nice Answer |
Oct 23 |
comment |
scheme of generalizations
@AndrewDudzik: the $U$ is always open as a rigid analytic subspace of $X_\eta^{an}$. |
Jul 3 |
awarded | Good Answer |
Jun 25 |
awarded | ac.commutative-algebra |
Jun 25 |
awarded | ag.algebraic-geometry |
Jun 25 |
awarded | ag.algebraic-geometry |
Jun 25 |
awarded | Revival |
Jun 21 |
comment |
Do all curves have Néron models
With Jilong Tong, we actually proved that the Néron model of any smooth projective geometrically connected curve of positive genus exists, and is equal to the smooth locus of the minimal proper regular model. |
Apr 25 |
revised |
When is Br(X) = H^2(X,G_m)?
Correct attribution. |
Apr 24 |
revised |
reduction types of elliptic curves
added 36 characters in body |
Apr 24 |
comment |
reduction types of elliptic curves
Thanks Will for the correction ! And III$^\star$ is a quadratic twist of III. |
Apr 24 |
revised |
reduction types of elliptic curves
added 29 characters in body |
Apr 24 |
answered | reduction types of elliptic curves |
Apr 12 |
revised |
scheme of generalizations
edited tags |
Apr 12 |
answered | scheme of generalizations |
Feb 26 |
comment |
Absorbing ramification and factoring finite flat maps
Each $Y_i$ is given by the subextension $K(Y_i)$ of $K(X)/K(Y)$. As $K(X)$ is finite separable over $K(Y)$, there are only finitely many subextensions. |
Feb 26 |
comment |
Absorbing ramification and factoring finite flat maps
(1) If there exists $Z\to Y$ faithfully flat such that $X\times_Y Z\to Z$ is étale, then by faithfully flat base change, $X\to Y$ is already étale ! |
Feb 25 |
comment |
The locus where a sheaf is supported in a certain dimension
Yes because in your special case $X\to T$ is proper. As for the reducedness (in the general case), apply your functor to all $U$ affine open in the (moduli scheme)$_{\mathrm{red}}$. |
Feb 25 |
comment |
The locus where a sheaf is supported in a certain dimension
As the fiber dimension doesn't change by base change, if there is a scheme which represents your functor, it will be reduced with underlying space equal to the set of $t\in T$ such that $\dim Z_t\le r$. If the latter is locally closed, then endow it with the structure of a reduced subscheme of $T$ and you get a scheme representing your functor. Otherwise I don't know, probably your functor is then not representable. |