Questions tagged [langlands-program]

In mathematics, the Langlands program is a web of far-reaching and influential conjectures about connections between number theory and geometry. Proposed by Robert Langlands (1967, 1970), it seeks to relate Galois groups in algebraic number theory to automorphic forms and representation theory of algebraic groups over local fields and adeles.

A grand unified theory of mathematics which includes the search for a generalization of Artin reciprocity (known as Langlands reciprocity) to non-Abelian Galois extensions of number fields. In a January 1967 letter to André Weil, Langlands proposed that the mathematics of algebra (Galois representations) and analysis (automorphic forms) are intimately related, and that congruences over finite fields are related to infinite-dimensional representation theory. In particular, Langlands conjectured that the transformations behind general reciprocity laws could be represented by means of matrices.

The Langlands program gives a very broad picture connecting automorphic forms and L-functions. It roughly states that, among other things, any L-function defined number-theoretically is the same as the one which can be defined as the automorphic L-function of some GL(n). In this loose way, every L-function is (conjecturally) viewed as one and the same object.

52 questions
11
votes
2 answers

Concrete example of non-abelian class field theory - why Langlands program *is* a non-abelian class field theory?

Abelian class field theory generalizes quadratic reciprocity laws for general number fields with abelian Galois groups, which connects class groups and Galois groups via Artin's reciprocity map. Also, quadratic reciprocity gives us some explicit…
7
votes
1 answer

Why is our definition of "smooth" function on a totally disconnected space the "right" definition?

My main interest in this comes from starting to learn about representations of totally disconnected, locally compact topological groups $G$, and their representations. I came across the definition of "smooth" functions $\phi:G\to \mathbb{C}$ as…
7
votes
1 answer

Which Hecke algebra is used in representation theory?

Which Hecke algebra is used in representation theory or more specifically in the study of Langlands's conjecture ? From here, the Hecke algebra is constructed from a locally compact topological group and its closed subgroup. While from here, the…
7
votes
0 answers

Do all cuspidal automorphic representations of $\operatorname{GL}_2(\mathbb A_{\mathbb Q})$ come from Maass or holomorphic cusp forms?

A normalized cuspidal newform $f$ (either holomorphic or Maass) can be identified with a function on $\phi: \operatorname{GL}_2(\mathbb Q) \backslash \operatorname{GL}_2(\mathbb A_{\mathbb Q})$, and it generates an irreducible cuspidal automorphic…
7
votes
1 answer

Results proved using perfectoid spaces understandable by an undergraduate

Many advanced areas of research in mathematics, the Riemann hypothesis, the Taniyama–Shimura conjecture, Green–Tao theorem etc. all have interesting consequences that could be stated using only undergraduate mathematics. Since perfectoid spaces are…
user34722
  • 379
7
votes
1 answer

Soft Question: in the Langlands program, which side is "geometric", which side is "spectral"?

I am in the process of ordering some book on the Langlands program, and learning more about it. In the mean time, I have a question which is easy to the experts, but being a beginner, I am not a 100% sure, so I could use some confirmation (or the…
Malkoun
  • 5,594
5
votes
1 answer

How to come up with the generating function of an elliptic curve?

Having watched the otherwise splendid Numberphile video with Edward Frenkel explaining the Langlands program, two mysteries remained completely open to me: Given the equation $y^2 + y = x^3 - x^2$ how would one ever come up in the first place with…
5
votes
0 answers

Why $(\mathfrak g_{\mathbb C},K)$-modules?

Let $G$ be a reductive group over $\mathbb Q$, $\mathfrak g=Lie(G)$ be its Lie algebra, $\mathfrak g\otimes_{\mathbb R} \mathbb C$ be its complexification. A definition of automorphic representation on $G$ is that it is an irreducible admissible…
5
votes
0 answers

How to recover abelian class field theory from Langlands?

I am reading about the Langlands program (mostly for fun). I am mostly self-taught in algebraic number theory. I have read that one recovers abelian class field theory from Langlands by setting $n=1$ so to speak, and looking at the group $G = GL_1$.…
5
votes
1 answer

Does the Langlands program preserve CFT's distinction between local and global theories?

This question is vaguely related to: Different formulations of Class Field Theory As I said there, I'm currently learning class field theory. For some motivation, I've also read a little about Langlands. Everything I've read about that program seems…
4
votes
0 answers

Coset representatives for $wPw^{-1} \cap P' \backslash P'$ for parabolic subgroups $P'$ and $P$?

I'm going through the calculation of the constant term of Eisenstein series in Moeglin and Waldsburger's Spectral Decomposition and Eisenstein series book (section II.1.7), and am confused on a small detail. Let $P = MN$ and $P' = M'N'$ be standard…
D_S
  • 35,843
3
votes
0 answers

Applications of Langlands for GLn Explicit reciprocity laws other than elliptic curves

Is there any explicit application of Langlands conjecture for $\mathrm{GL}(n)$ for $n \ge 3$, to get some reciprocity laws for higher dimensional varieties or higher genus curves? I've never found such things in articles such like "What is a…
3
votes
1 answer

Is the unramified local Langlands conjecture true?

I'm working on the unramified local Langlands conjecture and there is something that I don't understand if it is true or not. I want to start by saying that I don't care about endoscopic transfer or orbital integrals, but I just care about the…
3
votes
1 answer

$PGL_n(F)$ - Where to read about its (structure and) representation theory?

Ultimately, I'm interested in non-Archimedean local fields $F$, and am happy to take $\text{char}(F)=0$, and just focus on split $PGL_n(F)$. I suspect that the theory "more less" reduces to (smooth) representations of $GL_n(F)$ whose irreducible…
3
votes
1 answer

Quadratic reciprocity in Langlands program

I know quadratic reciprocity is the easiest example of langlands correspondence. Langlands correspondence gives some relation between automorphic forms and artin representations. My question is: what are the automorphic forms and the artin…
Tychonoff3000
  • 274
  • 1
  • 8
1
2 3 4