bio  website  perso.univstetienne.fr/… 

location  SaintEtienne, France  
age  33  
visits  member for  3 years, 5 months 
seen  9 hours ago  
stats  profile views  1,610 
I am currently a Maître de Conférences in SaintÉtienne, in France. I am particularly interested in Number Theory and Arithmetic Geometry.
2d

comment 
Why no abelian varieties over Z?
@ Emerton: but oddly enough, KhareWintenberger 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 modout 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 padic 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?
@MarianoSuárezAlvarez: 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?
deleted 1189 characters in body 