2,643 reputation
11332
bio website perso.univ-st-etienne.fr/…
location Saint-Etienne, France
age 33
visits member for 3 years, 5 months
seen 9 hours ago

I am currently a Maître de Conférences in Saint-Étienne, in France. I am particularly interested in Number Theory and Arithmetic Geometry.


2d
comment Why no abelian varieties over Z?
@ Emerton: but oddly enough, Khare-Wintenberger need an inductive argument whose basic step relies upon Schoof's work on abelian varieties over number field with few bad places... ;)
Mar
6
reviewed Reject Inverse of a matrix expression
Mar
6
reviewed Approve Averages over integer points of the sphere
Feb
25
comment Why is Class Field Theory the same as Langlands for GL_1?
@Kimball: I have downloaded the notes, but on page 115 you say that there is an isomorphisms between the idèle class group and the Galois group of $K^\text{ab}$, whereas I think you should mod-out by the connected component. This should create some discrepancy between "Galois characters" and "Hecke characters", no?
Feb
24
comment structure of norm one group for quadratic extension of p-adic fields
By definition, $U_E$ are the units, so all its elements are invertible...
Feb
9
reviewed Edit Rational subspaces
Feb
9
revised Rational subspaces
error in latex
Jan
27
reviewed Approve Besse p134 Riemann tensor in dimension 4
Jan
23
comment Is there a Galois correspondence for ring extensions?
Since I do not read russian, this might be the right place where to ask: are you aware of a generalization of the norm in a Galois extension of noncommutative algebras? Of course, if one treats central simple algebras, there is a reduced norm, but I am in a more general setting: $k$ a field, $B/A$ a finite (Galois?) extension of noncommutative $k$-algebras; and would like something like $\mathrm{Norm}_{B/A}\colon B^\times\to A^\times$.
Jan
23
comment Fixed field of the Nebentypus of a newform for $\Gamma_1(N)$
Oh, yes, I was sloppy with $L$ and $F$; thanks anyway.
Jan
23
comment Fixed field of the Nebentypus of a newform for $\Gamma_1(N)$
David, just one question: when you say that $F$ is evidently $\mathbf{Q}(i)$, do you really mean that or simply that it is very much reasonable to guess from the first five coefficients? Of course, this does not affect your argument, but just to know.
Jan
22
reviewed Approve Proof of a cubic equation problem
Jan
21
reviewed Reject When does the homological dimension of a tensor product equal the sum of dimensions?
Jan
14
answered Examples of great mathematical writing
Jan
14
awarded  Electorate
Jan
13
reviewed Approve On $e^{\pi\sqrt{4\cdot163}}$ and unusual connections
Dec
30
reviewed Approve What are the values of this sequence?
Dec
30
comment Localizations or quotients of categories?
@MarianoSuárez-Alvarez: ok, I see. Although already not bad (and in any case more than I could have done), can you think of an "explicit" example which occurs somewhere (or an application of yours)?
Dec
30
comment Localizations or quotients of categories?
Thanks, Quillen indeed ciotains the answer I was looking for. As an aisde, do you have any idea of occurrencies of "moding out homs by relations" which has nothing to do with localizations, as you say at the very beginning of your answer?
Dec
30
revised Localizations or quotients of categories?
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