MathOverflow will be down for maintenance for approximately 3 hours, starting Monday evening (06/24/2013) at approximately 9:00 PM Eastern time (UTC-4).

Joël

10,389
Reputation
6969 views
Is this your account?

Registered User 

Name Joël
Member for 2 years
Seen 1 hour ago
Website
Location Stony Creek, Branford, CT, États-Unis
Age
Professor of Mathematics at Brandeis University
Jun
14
accepted Does every equivalence class of Hecke characters contain a distinguished element?
Jun
14
comment Does every equivalence class of Hecke characters contain a distinguished element?
@Kconrad: you're right. $n$ is the degree of $k$ over $\mathbb Q$. I have edited my answer to say this. @Daniel: the map $i$ is canonical. The only freedom you have in defining the isomorphism of $\R$-\algebras $k \otimes_{\mathbb Q} \mathbb R \simeq \mathbb R^{r_1} \times \mathbb C^{r_2}$ is that you can let act the complex conjugacy on each of the $\mathbb C$ factors (hence you have $2^{r_2}$ such isomorphisms). But as far as the embedding of $\R$ is concern, this choice does not change anything.
Jun
14
revised Does every equivalence class of Hecke characters contain a distinguished element?
added 148 characters in body
Jun
13
comment Analysis of the boundary of the Mandelbrot set
Why the vote to close? The question makes senses. It might have a trivial answer, but I, for one, would be happy to know it...
Jun
13
answered Does every equivalence class of Hecke characters contain a distinguished element?
Jun
12
answered Independence of an interval and a product set in $\mathbb Z/L\mathbb Z$.
Jun
11
revised Hecke equidistribution
edited tags
Jun
11
awarded  Enlightened
Jun
11
awarded  Nice Answer
Jun
11
awarded  Fanatic
Jun
11
comment Heuristic for Montgomery’s conjecture
Dear Dimitris, thanks for your answer. Even if it is not exactly what I asked, this is more or less what I needed. Actually, I recently noticed that some non-abelian generalizations of Montgomery's conjecture (suggered by Murty and Murty) are false (I didn't want then to be false, I swear-- I wanted to apply them: but they gave me too strong results to be true). Now I am trying to understand what goes wrong, in order to get a conjecture that might be correct. I will try to work out what this heuristics give in the non-abelian case, and see what comes out.
Jun
11
revised Extensions of Galois representations
typos corrected
Jun
11
comment Independence of an interval and a product set in $\mathbb Z/L\mathbb Z$.
Interesting. So my question would be a dynamical system question, kind of... But I don't understand what you mean by: "use Cauchy-Schwarz inequality to complete the variable"
Jun
10
answered Why is it a good idea to study a ring by studying its modules?
Jun
10
asked Independence of an interval and a product set in $\mathbb Z/L\mathbb Z$.
Jun
10
revised Extensions of Galois representations
deleted 286 characters in body
Jun
10
revised Extensions of Galois representations
added 320 characters in body
Jun
10
accepted Extensions of Galois representations
Jun
10
revised Extensions of Galois representations
added 456 characters in body; added 7 characters in body; added 63 characters in body
Jun
10
revised Extensions of Galois representations
edited tags
Jun
10
answered Extensions of Galois representations
Jun
9
accepted Galois deformations with Panchiskin condition
Jun
8
comment What is the source of this famous Grothendieck quote?
This is an interesting quote. Yet the idea that definitions are the most important "vehicles" of mathematical rigor is very old, and has been perfectly expressed already by Pascal in "l'art de persuader". A more original idea is the one of Grothendieck, that definition may have an even higher role in mathematics, as vehicle not only of rigor, but of mathematical creativity itself. That is, the creative work of a mathematicians is not mainly to prove good theorems, it is to "invent" good definitions. His works are a sufficient illustration of this new maxim.
Jun
8
comment What is the source of this famous Grothendieck quote?
For what it's worth: I have read "récoltes et semailles" years ago, but this quote doesn't ring any bell. – Joël 0 secs ago
Jun
8
revised Primes in short intervals with a preassigned frobenius
added 1353 characters in body
Jun
7
revised Primes in short intervals with a preassigned frobenius
deleted 1305 characters in body
Jun
7
comment Primes in short intervals with a preassigned frobenius
You're both right. I will reformulate my question...
Jun
7
revised Primes in short intervals with a preassigned frobenius
edited tags
Jun
7
answered Roadmap to reach Arithmetic Geometry for a Physics Major
Jun
7
asked Primes in short intervals with a preassigned frobenius
Jun
7
awarded  Citizen Patrol
Jun
7
comment Principal series of finite group of Lie type
Thanks for giving these details.
Jun
7
comment Principal series of finite group of Lie type
Thanks to all three of you, Matt, Jim and Jay. After a crash self-course on Deligne-Luztig theory (how beautiful!), I now understand your arguments, which are basically the same.
Jun
6
comment Principal series of finite group of Lie type
I stay tuned. Thanks already.
Jun
6
revised Principal series of finite group of Lie type
added 1 characters in body
Jun
6
asked Principal series of finite group of Lie type
Jun
5
asked Heuristic for Montgomery’s conjecture
Jun
5
awarded  Nice Answer
Jun
5
answered Modular symbols and degeneracy maps
Jun
5
comment Modular symbols and degeneracy maps
You're asking if the Ihara's lemma is true in the context of modular symbols...
Jun
3
comment Is Gouvêa-Mazur’s “Infinite Fern” a fractal?
I think the question is interesting, but somehow is still not well-posed. There is the problem of what is a fractal, discussed in earlier comments, but also the problem of what is the "infinite fern". I mean, it is a rigid analytic varieties, but there are at least three ways to formalize this notion, Tate's and Berkovich's and Huber's. Each leads to a different space..
Jun
1
accepted Examples of (Phi,Gamma)-modules
May
31
answered Effective Chebotarev without Artin’s conjecture
May
30
revised Examples of (Phi,Gamma)-modules
added 1213 characters in body
May
30
answered Galois deformations with Panchiskin condition
May
29
answered Examples of (Phi,Gamma)-modules
May
29
answered etale cohomology of an abelian variety and its dual
May
28
accepted Would a proof of Ramanujan Conjecture together with other known results about automorphic L-functions imply the Grand Riemann Hypothesis?
May
28
answered Would a proof of Ramanujan Conjecture together with other known results about automorphic L-functions imply the Grand Riemann Hypothesis?
May
25
comment Effective Chebotarev without Artin’s conjecture
Dear Frank: yes, I have been playing with that circle of ideas since a while. IK state without ambiguity that the strong formula (the one which implies an error term in square root of the size of the conjugacy set) holds with just GRH, without Artin. They may have meant otherwise but this is what they write. I have started a bounty to give this question more visibility, hoping that someone would help us resolve this situation: a strong result appearing in the (main stream) literature but for which no proof is to be found.