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Grothendieck-Teichmüller conjecture

(1) In "Esquisse d'un programme", Grothendieck conjectures Grothendieck-Teichmüller conjecture: the morphism $$ G_{\mathbb{Q}} \longrightarrow Aut(\widehat{T}) $$ is an isomorphism. Here $...
AFK's user avatar
  • 7,527
12 votes
0 answers
811 views

Number field analog of Artin-Tate $\Rightarrow$ BSD?

What is the difference between the alternating product of the Hasse-Weil $L$-functions of the generic fiber of an arithmetic scheme $X\to\text{Spec}(\mathbf{Z})$ and the zeta function of $X$? (each ...
user avatar
11 votes
0 answers
1k views

Linear algebra of elliptic curves over p-adic fields

Unfortunately, the following question is somewhat ill-posed. However, I hope to make what I'm looking for sufficiently clear. Given two elliptic curves (or Abelian varieties) over $\mathbb{C}$, one ...
Moosbrugger's user avatar
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10 votes
0 answers
350 views

How are the hypergeometric motives of WZ-Pairs connected?

If $\small{(F,G)}$ is a WZ-pair and general asymptotic conditions $\lim_{k\rightarrow\infty}\small{G(n,k)=0}$ and $\lim_{n\rightarrow\infty}\small{F(n,k)=0}$ hold, then we have the certified ...
Jorge Zuniga's user avatar
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10 votes
0 answers
481 views

What is the precise definition of "Hypergeometric motives over $\mathbb{Q}$"?

The question is as in the title, but here is some background: Section 4 of this paper by Beukers, Cohen and Mellit is called "Hypergeometric motive over $\mathbb{Q}$" but no actual (pure) ...
naf's user avatar
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10 votes
0 answers
340 views

Geometric vs combinatorial motives over Spec Z

Consider the category of reduced schemes of finite type over $\mathbb{Z}$. Take the Grothendieck group of this category, i.e. the free abelian group on isomorphism classes, modulo the usual "syzygy" ...
Andreas Holmstrom's user avatar
9 votes
0 answers
291 views

Searching for hypergeometric motives that split

Motivation: It seems that the splitting of a hypergeometric motive is closely related to some highly non-trivial hypergeometric identities discovered by Ramanujan, Guillera et al. The splitting of ...
Y. Zhao's user avatar
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9 votes
0 answers
649 views

Motivic fundamental group of the moduli space of curves?

Suppose I have a smooth projective family of varieties of varieties over $\mathcal M_g$ - i.e. a universal functor, commuting with deformations, from curves to smooth projective varieties. Can I ...
Will Sawin's user avatar
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8 votes
0 answers
375 views

Computing motivic Galois group

Suppose I have a motive $M$ over $\mathbb{Q}$, and can compute the Euler factor of the associated $L$-function for any good prime $p$. How can I compute the Zariski closure of the image of the Galois ...
Watson Ladd's user avatar
  • 2,429
8 votes
0 answers
603 views

A Generalization of the Tate-Shafarevich/Tate/Fontaine-Mazur Conjectures

Let $A$ be an abelian variety over a number field $k$. The Tate-Shafarevich conjecture says that the Tate-Shafarevich group of $A$ is finite. A weakening of this conjecture states that the $\ell$-...
David Corwin's user avatar
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7 votes
0 answers
444 views

Status of the conjectured vanishing of Bloch-Kato H^2

There is a folklore conjecture that $\operatorname{Ext}^2$ vanishes in the category of geometric $p$-adic Galois representations (i.e. representations that are unramified almost everywhere and de Rham ...
David Corwin's user avatar
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7 votes
0 answers
279 views

Quadratic twists of 1-motives

Quadratic twists of elliptic curves (or, more generally, abelian varieties) are familiar objects in arithmetic geometry. I would like to extend that definition to the category of 1-motives over global ...
Cristian D. Gonzalez-Aviles's user avatar
6 votes
0 answers
221 views

Motives in tropical geometry

Is there a notion of motives in tropical geometry? Similar like the notion introduced by Grothendieck in algebraic geometry.
Raoul's user avatar
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5 votes
0 answers
210 views

Motivic $L$-functions came from automorphic representations

Langlands in his 1978 ICM talk made a conjecture that all motivic $L$-functions should arise as automorphic $L$-functions. A part of this conjecture, namely for some Hasse-Weil $\zeta$ functions is a ...
coLaideronnette's user avatar
5 votes
0 answers
275 views

Reference request: Tate's conjecture for L functions of motives

What's a good reference for the most general form of Tate's conjecture for the order of poles of the L function of a motive? Thanks!
Ramin's user avatar
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5 votes
0 answers
654 views

The Shafarevich Conjecture and motivic Langlands stacks.

Hi, I recently learned about an amazing conjecture of Shafarevich (proved by Faltings) about the finiteness of the number of curves of a fixed genus with good reduction outside a finite number of ...
Spaghetti Inks's user avatar
5 votes
0 answers
834 views

Motivic Galois group and Shimura varieties

Hi, Suppose that one has a Shimura variety $Sh(G,X)$ where $(G,X)$ is the corresponding Shimura datum and suppose that it can be interpreted as a moduli space of motives (e.g. PEL type Shimura ...
unknown's user avatar
  • 647
4 votes
0 answers
219 views

Generate periods only by smooth varieties

Like explained in this passage that a period is a complex number whose real and imaginary parts are integrations of rational functions over $\mathbb{Q}$ on some $\mathbb{Q}$-semi-algebra set in $\...
CO2's user avatar
  • 275
4 votes
0 answers
293 views

Galois representation with infinite image but finite image everywhere locally

Fix a prime $l$. Let $\phi:\mathrm{Gal}(\overline{\mathbb{Q}}/\mathbb{Q})\to GL_n(\mathbb{Q}_l)$ be a semisimple continuous representation. Assume $\phi$ has finite image when restricted to $\mathrm{...
user avatar
4 votes
0 answers
168 views

Derived weight filtration on motivic Galois representations

Thanks to modern techniques (such as the pro-etale site), we can now understand etale (co)homology of varieties and motives as "genuinely" derived (e.g. DG) Galois-equivariant objects. I'm looking for ...
Dmitry Vaintrob's user avatar
4 votes
0 answers
232 views

holomorphic continuation of motivic $L$-functions

The question is rather easy to formulate: when is the $L$-function of a pure motive over $\mathbb{Q}$ expected to have a holomorphic (as opposed to simply meromorphic) continuation to the complex ...
lfu's user avatar
  • 41
4 votes
0 answers
192 views

A question on Nekovar's paper Belinson's Conjectures

In Section 2 of Nevovar's paper "Beilinson's Conjectures", for a pure motive $M$ of the form $h^i(X)(n)$ where $X$ is a projective smooth variety over $\mathbb{Q}$ and $n$ is an integer such that the ...
Wenzhe's user avatar
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3 votes
0 answers
143 views

A Galois equivariant Weil cohomology theory with coefficients in the rational numbers and a variation of the Tate/Hodge conjecture

A well-known example of Serre shows that there can be no Weil cohomology theory with $\mathbb Q$ coefficients for schemes over $\mathbb F_{p^2}$. However, this example is no obstruction to a Weil ...
Asvin's user avatar
  • 7,746
3 votes
0 answers
128 views

On Abhyankar's results cited in a paper of Manin titled "Correspondences, Motifs and Monoidal Transformations"

Consider the following from this paper "Correspondences, Motifs and Monoidal Transformations" of Manin here. Theorem. Nonsingular three-dimensional projective unirational varieties $V$ over ...
user100749's user avatar
2 votes
0 answers
151 views

Compatibility of system of $\ell$-adic representations associated to Voevodsky motives

Let $M$ be an object of Voevodsky's category $DM_{gm}(K,\mathbb{Q})$ for a number field $K$. For each prime number $\ell$, there is an $\ell$-adic realization $M_{\ell}$ in the bounded derived ...
David Corwin's user avatar
  • 15.4k
2 votes
0 answers
148 views

Analytic properties of motivic L-functions twisted by Dirichlet characters

Let $M$ be a pure motive over $\mathbb{Q}$ and consider the (completed) $L$-function $\Lambda(M, s)$ attached to its $\ell$-adic realization. Let us assume that this $L$-function admits analytic ...
tbg93dk's user avatar
  • 83
2 votes
0 answers
223 views

Residual Representation of a Motive

Suppose we have $M$ a hypergeometric motive, and $\rho$ its associated Galois rep over $\mathbb{Q}_{l}$. Is there any easy/concrete way to find $\bar{\rho}$, the residual representation at a prime (in ...
Watson Ladd's user avatar
  • 2,429
0 votes
0 answers
328 views

Mixed motives and motivic cohomology

In Scholl's paper "Remarks on special values of $L$-functions", he defines that an object $M$ of $\textbf{MM}_{\mathbb{Q}}$ (the conjectured abelian category of mixed motives with coefficients $\...
Wenzhe's user avatar
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