Algorithmic construction of Shimura - Taniyama - Weil parametrization of elliptic curves over the rationals

Virtues of Priority

The conjecture that every elliptic curve with rational coefficients is a so-called modular curve -- since 2000 a theorem due in large part to Andrew Wiles and, in complete generality, to Breuil-Conrad-Diamond-Taylor -- has been known by various names: Weil Conjecture, Taniyama-Weil Conjecture, Shimura-Taniyama-Weil Conjecture, or Shimura-Taniyama Conjecture, among others. The question of the authorship of this conjecture, one of whose corollaries is Fermat's Last Theorem, has been the subject of a priority dispute that has often been quite bitter, but the principles behind one attribution or a…

Belyi parametrisations of elliptic curves and congruence defects

In this note we consider questions about parametrisations of elliptic curves defined over number fields by quotients of the upper half-plane by finite index subgroups of SL_2(Z). We ask if we can choose such a parametrisation of an elliptic curve to reflect the field over which it is defined: this can be viewed as a generalisation of the Shimura-Taniyama-Weil conjecture.

Zero-dimensional Shimura varieties and central derivatives of Eisenstein series

We formulate and prove a version of the arithmetic Siegel-Weil formula for (zero dimensional) Shimura varieties attached to tori, equipped with some additional data. More precisely, we define a family of ``special" divisors in terms of Green functions at archimedean and non-archimedean places, and prove that their degrees coincide with the Fourier coefficients of the central derivative of an Eisenstein series. The proof relies on the usual Siegel-Weil formula to provide a direct link between both sides of the identity, and in some sense, offers a more conceptual point of view on prior results …

On the arithmetic Siegel--Weil formula for GSpin Shimura varieties

We formulate and prove a local arithmetic Siegel--Weil formula for GSpin Rapoport--Zink spaces, which is a precise identity between the arithmetic intersection numbers of special cycles on GSpin Rapoport--Zink spaces and the derivatives of local representation densities of quadratic forms. As a first application, we prove a semi-global arithmetic Siegel--Weil formula as conjectured by Kudla, which relates the arithmetic intersection numbers of special cycles on GSpin Shimura varieties at a place of good reduction and the central derivatives of nonsingular Fourier coefficients of incoherent Sie…

Generating series of intersection volumes of special cycles on unitary Shimura varieties

We form a generating series of regularized volumes of intersections of special cycles on a non-compact unitary Shimura variety with a fixed base change cycle. We show that it is a Hilbert modular form by identifying it with a theta integral, which we show converges even though the parameters lie outside the classical convergence range of Weil. By applying the regularized Siegel-Weil formulas of Ichino and Gan-Qiu-Takeda, we show the modular form is the restriction of a hermitian modular form of degree n related to Siegel Eisenstein series on U(n,n). An essential fact used is a computation show…

Green forms and the arithmetic Siegel-Weil formula

We construct natural Green forms for special cycles in orthogonal and unitary Shimura varieties, in all codimensions, and, for compact Shimura varieties of type O(p,2) and U(p,1), we show that the resulting local archimedean height pairings are related to special values of derivatives of Siegel Eisentein series. A conjecture put forward by Kudla relates these derivatives to arithmetic intersections of special cycles, and our results settle the part of his conjecture involving local archimedean heights.

Newton polygons of cyclic covers of the projective line branched at three points

We review the Shimura-Taniyama method for computing the Newton polygon of an abelian variety with complex multiplication. We apply this method to cyclic covers of the projective line branched at three points. As an application, we produce multiple new examples of Newton polygons that occur for Jacobians of smooth curves in characteristic $p$. Under certain congruence conditions on $p$, these include: the supersingular Newton polygon for each genus $g$ with $4 \leq g \leq 11$; nine non-supersingular Newton polygons with $p$-rank $0$ with $4 \leq g \leq 11$; and, for all $g \geq 5$, the Newton p…

A genus two arithmetic Siegel-Weil formula on X_0(N)

We define a family of arithmetic zero cycles in the arithmetic Chow group of a modular curve X_0(N), for N>3 odd and squarefree, and identify the arithmetic degrees of these cycles as q-coefficients of the central derivative of a Siegel Eisenstein series of genus two. This parallels work of Kudla-Rapoport-Yang for Shimura curves.

Patching and Multiplicity $2^k$ for Shimura Curves

We use the Taylor-Wiles-Kisin patching method to investigate the multiplicities with which Galois representations occur in the mod $\ell$ cohomology of Shimura curves over totally real number fields. Our method relies on explicit computations of local deformation rings done by Shotton, which we use to compute the Weil class group of various deformation rings. Exploiting the natural self-duality of the cohomology groups, we use these class group computations to precisely determine the structure of a patched module in many new cases in which the patched module is not free (and so multiplicity on…

关于具有非准分裂局部群的简单Shimura簇的上同调

On the cohomology of simple Shimura varieties with non quasi-split local groups

本文研究了非准分裂局部群下简单Shimura簇坏约化的Scholze测试函数，证明了其扭曲轨道积分的消没性质及伪稳定基变换的存在性，并推导出在稳定迹公式和局部Hasse-Weil zeta函数中的应用。

On Shimura curves in the Schottky locus

We show that a given rational Shimura curve Y with strictly maximal Higgs field in the moduli space of g-dimensional abelian varieties does not generically intersect the Schottky locus for large g. We achieve this by using a result of Viehweg and Zuo which says that if Y parameterizes a family of curves of genus g, then the corresponding family of Jacobians is isogenous over Y to the g-fold product of a modular family of elliptic curves. After reducing the situation from the field of complex numbers to a finite field, we will see, combining the Weil and Sato-Tate conjectures, that this is impo…

Shimura 曲线上的特殊循环交集与Siegel Maass形式

Intersections of special cycles on Shimura curves and Siegel Maass forms

本文研究Shimura曲线上的特殊循环交集与Siegel Maass形式的关系，通过非全纯模形式和theta提升方法，推广了Rickards的计数结果，并给出了傅里叶系数的几何解释。

The Test Function Conjecture for Local Models of Weil-restricted groups

We prove the test function conjecture of Kottwitz and the first named author for local models of Shimura varieties with parahoric level structure attached to Weil-restricted groups, as defined by B. Levin. Our result covers the (modified) local models attached to all connected reductive groups over $p$-adic local fields with $p\geq 5$. In addition, we give a self-contained study of relative affine Grassmannians and loop groups formed using general relative effective Cartier divisors in a relative curve over an arbitrary Noetherian affine scheme.

酉 Shimura 簇的算术特殊除子的模性（附录由 Yujie Xu 撰写）

Modularity of arithmetic special divisors for unitary Shimura varieties (with an appendix by Yujie Xu)

本文构造了任意分裂水平下酉 Shimura 簇整模型上 Kudla 特殊除子算术扩张的显式生成级数，利用容许算术除子理论与算术混合 Siegel-Weil 公式证明其模性，部分解决了 Kudla 模问题。

Chow motives associated to certain algebraic Hecke characters

Shimura and Taniyama proved that if $A$ is a potentially CM abelian variety over a number field $F$ with CM by a field $K$ linearly disjoint from F, then there is an algebraic Hecke character $λ_A$ of $K$ such that $L(A/F,s)=L(λ_A,s)$. We consider a certain converse to their result. Namely, let $A$ be a potentially CM abelian variety appearing as a factor of the Jacobian of a curve of the form $y^e=γx^f+δ$. Fix positive integers $a$ and $n$ such that $n/2 < a \leq n$. Under mild conditions on $e, f, γ, δ$, we construct a Chow motive $M$, defined over $F=\mathbb{Q}(γ,δ)$, such that $L(M/F,s)$ a…

On the cohomology of compact unitary group Shimura varieties at ramified split places

In this article, we prove results about the cohomology of compact unitary group Shimura varieties at split places. In nonendoscopic cases, we are able to give a full description of the cohomology, after restricting to integral Hecke operators at p on the automorphic side. We allow arbitrary ramification at p; even the PEL data may be ramified. This gives a description of the semisimple local Hasse-Weil zeta function in these cases. We also treat cases of nontrivial endoscopy. For this purpose, we give a general stabilization of the expression given in previous work, following the stabilization…

几何单位元Kudla猜想

The Geometric Unitary Kudla Conjecture

本文基于几何单位元Kudla猜想，证明对称形式傅里叶-雅科比级数收敛并等于Hermitian Hilbert模形式的展开，验证了猜想并在任意余维数上去除Li-Liu的算术内积公式的模性假设。

Heegner points and the rank of elliptic curves over large extensions of global fields

Let k be a global field, $\bar{k}$ a separable closure of k, and $G_k$ the absolute Galois group $\Gal(\bar{k}/k)$ of $\bar{k}$ over k. For every g in $G_k$, let $\bar{k}^g$ be the fixed subfield of $\bar{k}$ under g. Let E/k be an elliptic curve over k. We show that for each g in $G_k$, the Mordell-Weil group $E(\bar{k}^g)$ has infinite rank in the following two cases. Firstly when k is a global function field of odd characteristic and E is parametrized by a Drinfeld modular curve, and secondly when k is a totally real number field and E/k is parametrized by a Shimura curve. In both cases our…

McMullen曲线、Weil位移以及Abelian六折的Hodge猜想

McMullen's Curve, the Weil Locus, and the Hodge Conjecture for Abelian Sixfolds

研究McMullen曲线与Weil位移在Abelian六折中的性质，证明其交点为有限且可能为空，揭示Hodge-Weil类的特殊性及Hodge猜想的新案例。