activity
20162026
most citedPicard ranks of K3 surfaces over function fields and the Hecke orbit conjecture

14 citations · 67 across the 20 of their papers we have counts for

collaborators

22 papers

math.NT2026

S-integrality for families of ordinary K3 surfaces and algebraicity theorems

Ruofan Jiang, Ananth N. Shankar

We prove an -integrality theorem for special divisors on GSpin Shimura varieties in positive characteristic. Let be a generically ordinary curve in such a Shimura variety no…

math.AG2025

Powers of abelian varieties over not isogenous to a Jacobian

Olivier de Gaay Fortman, Ananth N. Shankar

We prove the existence of abelian varieties over with no power isogenous to a Jacobian. Moreover, given a positive integer , we prove the existence of…

math.NT2025

Finiteness of function field-valued points on exceptional Shimura varieties

Benjamin Bakker, Ananth N. Shankar, Jacob Tsimerman

Let be a smooth curve over a finite field of characteristic . We prove that there are finitely many principally polarized abelian schemes of given dimension over …

math.NT2025

-adic hyperbolicity for Shimura varieties and period images

Benjamin Bakker, Abhishek Oswal, Ananth N. Shankar +1

We prove that Shimura varieties and geometric period images satisfy a -adic extension property for large enough primes . More precisely, let $\mathsf{D}^{\times}\subset \math…

math.NT2025

A characteristic p analogue of the André--Pink--Zannier conjecture

Yeuk Hay Joshua Lam, Ananth N. Shankar

We investigate the analogue of the André--Pink--Zannier conjecture in characteristic . Precisely, we prove it for ordinary function field-valued points with big monodromy, in Sh…

math.NT2024★ 1 cited

Integral canonical models of exceptional Shimura varieties

Benjamin Bakker, Ananth N Shankar, Jacob Tsimerman

We prove that Shimura varieties admit integral canonical models for sufficiently large primes. In the case of abelian-type Shimura varieties, this recovers work of Kisin-Kottwitz f…

math.NT2023

-adic hyperbolicity for moduli spaces of abelian motives

Abhishek Oswal, Ananth N. Shankar, Xinwen Zhu +1

We prove that Shimura varieties of abelian type satisfy a -adic Borel-extension property over discretely valued fields. More precisely, let denote the rigid-analyti…

math.AG2022★ 1 cited

Just-likely intersections on Hilbert modular surfaces

Asvin G., Qiao He, Ananth N. Shankar

In this paper, we prove an intersection-theoretic result pertaining to curves in certain Hilbert modular surfaces in positive characteristic. Specifically, we show that given two a…

math.NT2021

Finiteness of reductions of Hecke orbits

Mark Kisin, Yeuk Hay Joshua Lam, Ananth N. Shankar +1

We prove two finiteness results for reductions of Hecke orbits of abelian varieties over local fields: one in the case of supersingular reduction and one in the case of reductive m…

math.NT2021★ 3 cited

Canonical Heights on Shimura Varieties and the André-Oort Conjecture

Jonathan Pila, Ananth N. Shankar, Jacob Tsimerman +2

The main purpose of this work is to prove the André-Oort conjecture in full generality.

math.NT2021

Abelian varieties not isogenous to Jacobians over global fields

Ananth N. Shankar, Jacob Tsimerman

We prove the existence of abelian varieties not isogenous to Jacobians over characterstic function fields. Our methods involve studying the action of degree Hecke operators…

math.NT2020★ 14 cited

Picard ranks of K3 surfaces over function fields and the Hecke orbit conjecture

Davesh Maulik, Ananth N. Shankar, Yunqing Tang

Let be a non-isotrivial and generically ordinary family of K3 surfaces over a proper curve in characteristic . We prove that the geometric…

math.NT2019★ 13 cited

Exceptional jumps of Picard ranks of reductions of K3 surfaces over number fields

Ananth N. Shankar, Arul Shankar, Yunqing Tang +1

Given a K3 surface over a number field with potentially good reduction everywhere, we prove that the set of primes of where the geometric Picard rank jumps is infinite.…

math.NT2019★ 1 cited

Families of elliptic curves ordered by conductor

Ananth N. Shankar, Arul Shankar, Xiaoheng Wang

In this article, we study the family of elliptic curves , having good reduction at and , and whose -invariants are small. Within this set of elliptic curves…

math.NT2019★ 13 cited

Almost ordinary abelian varieties over finite fields

Abhishek Oswal, Ananth N. Shankar

We provide a characterization of almost ordinary abelian varieties over finite fields, and use this characterization to provide lower bounds for the sizes of some almost ordinary i…

math.NT2018

Reductions of abelian surfaces over global function fields

Davesh Maulik, Ananth N. Shankar, Yunqing Tang

Let be a non-isotrivial ordinary abelian surface over a global function field with good reduction everywhere. Suppose that does not have real multiplication by any real qua…

math.NT2018

The rank two -curvature conjecture on generic curves

Anand Patel, Ananth N. Shankar, Junho Peter Whang

We prove the -curvature conjecture for rank two vector bundles with connection on generic curves, by combining deformation techniques for families of varieties and topological a…

math.NT2017★ 11 cited

Exceptional splitting of reductions of abelian surfaces

Ananth N. Shankar, Yunqing Tang

Heuristics based on the Sato--Tate conjecture suggest that an abelian surface defined over a number field has infinitely many places of split reduction. We prove this result for ab…

math.NT2016★ 5 cited

Serre-Tate theory for Shimura varieties of Hodge type

Ananth N. Shankar, Rong Zhou

We study the formal neighbourhood of a point in -ordinary locus of an integral model of a Hodge type Shimura variety. We show that this formal neighbourhood has a structure of a…

math.NT2016★ 1 cited

2-Selmer groups of hyperelliptic curves with two marked points

Ananth N. Shankar

We consider the family of hyperelliptic curves over $\Q$ of fixed genus along with a marked rational Weierstrass point and a marked rational non-Weierstrass point. When these curve…

math.NT2016★ 4 cited

The -curvature conjecture and monodromy about simple closed loops

Ananth N. Shankar

The Grothendieck-Katz -curvature conjecture is an analogue of the Hasse Principle for differential equations. It states that a set of arithmetic differential equations on a vari…

math.NT2016

Unlikely Intersections in Finite Characteristic

Ananth N Shankar, Jacob Tsimerman

We present a heuristic argument based on Honda-Tate theory against many conjectures in `unlikely intersections' over the algebraic closure of a finite field; notably, we conjecture…