Skip to main content

All Questions

Filter by
Sorted by
Tagged with
3 votes
1 answer
131 views

Depth of the filtration of higher ramification groups in the ramified case in Serre's modularity conjecture

I am studying Serre's paper "Sur les représentations modulaires de degré 2 de $\mathrm{Gal(\overline{\mathbb Q}/\mathbb Q)}$" and I have some questions about Serre's definition of "peu ...
Marta Sánchez Pavón's user avatar
1 vote
0 answers
124 views

A question related to Kirillov model

I am reading Jackson - The theory of admissible representations of $\operatorname{GL}(2, F)$ and am not able to understand the following map related to Kirillov model. This result appears on p. 54: I ...
user15243's user avatar
  • 424
8 votes
1 answer
567 views

Symmetric power lift of modular forms

Let $f_1$ and $f_2$ be two cuspforms of weights $k_1$ and $k_2$ and nebentypus $\epsilon_1$ and $\epsilon_2$ respectively such that $f_1 \neq f_2 \otimes \chi$ for some Dirichlet character $\chi$ of ...
user15243's user avatar
  • 424
5 votes
2 answers
237 views

Irreducibility of the $n$th symetric power of the reduction of the Galois representation of a non-CM newform

In "On $\ell$-adic representations attached to modular forms II", Ribet proved that the $\ell$-adic representation $\rho_{f,\ell}$ attached to a non-CM newform form $f$ satisfies $${\rm SL}...
Fouad Fahmi's user avatar
5 votes
0 answers
132 views

Field of definition of compatible system of Galois representations

Let $K,F$ be number fields and suppose that there is a compatible system of Galois representations $$(\rho_{\lambda} : \text{Gal}(\overline{K}/K) \longrightarrow \text{GL}_n(\overline{F}_\lambda) )$$ ...
Sun Ra's user avatar
  • 173
1 vote
0 answers
138 views

Hilbert modular form as a representation of Hecke algebra

I am reading some notes by Snowden and I don't understand a sentence. Clearly, if we have an appropriate $R = T$ theorem then we get a modularity lifting theorem, as $\rho$ defines a homomorphism ...
JonasP's user avatar
  • 11
9 votes
1 answer
507 views

A question about Galois representations

Let $K$ be a number field and $(\rho,V)$, $(\rho',V')$ be two Galois representations of $\mathrm{Gal}(\overline{\mathbb{Q}}/K)$. Suppose that for some positive integer $n$ we have $\mathrm{Sym}^n\rho\...
User1930752648's user avatar
2 votes
0 answers
138 views

Local polynomials of Frobenius-semisimple Weil representations which are tensor products of an Artin representation and an unramified character

Let $K$ be a local field and $\rho: W_K \to \operatorname{GL}(V)$ be a Weil representation. The for any finite extension $F/K$, we define the local polynomial $$ P(\rho|_F,T) = \det{(1 - \operatorname{...
Diglett's user avatar
  • 103
1 vote
0 answers
105 views

Local factors determine Weil representations - proof of the Artin representation case

This post can be seen as a continuation of this post I created on MathOverflow. I want to understand the proof of the following Theorem from "Euler Factors determine Weil Representations" by Tim and ...
Diglett's user avatar
  • 103
2 votes
1 answer
317 views

Local factors determine Weil representations - proof of the cyclic case

I already created this post on Math Stack Exchange but I was not so sure if this question fits better here. If it is not, I want to apologize in advance and feel free to delete my post. I want to ...
Diglett's user avatar
  • 103
3 votes
0 answers
199 views

Decompositions of representations of pro-p groups

Let $P$ be a pro-p group. Assume that there is a filtration of $P$ by normal subgroups $P_i$ such that $P_0=P$ and $P_{i+1} < P_i(i\in\mathbb N)$. Let $V$ be an $l$-adic representation of $P$, ...
Int's user avatar
  • 93