papers

Publications (18)

math.NT2025

Mod gamma factors and a converse theorem for finite general linear groups

Jacksyn Bakeberg, Mathilde Gerbelli-Gauthier, Heidi Goodson +3

The local converse theorem for Rankin-Selberg gamma factors of proved by Piatetski-Shapiro over no longer holds after reduction modulo $\…

math.NT2021

A Galois-dynamics correspondence for unicritical polynomials

Robin Zhang

In an analogy with the Galois homothety property for torsion points of abelian varieties that was used in the proof of the Mordell-Lang conjecture, we describe a correspondence bet…

math.AG2018

Section rings of -divisors on minimal rational surfaces

Aaron Landesman, Peter Ruhm, Robin Zhang

We give bounds on the degree of generation and relations of section rings associated to arbitrary -divisors on projective spaces of all dimensions and Hirzebruch surfac…

cs.DC2026

Scalable Training of Mixture-of-Experts Models with Megatron Core

Zijie Yan, Hongxiao Bai, Xin Yao +42

Scaling Mixture-of-Experts (MoE) training introduces systems challenges absent in dense models. Because each token activates only a subset of experts, this sparsity allows total pa…

math.AG2016

Spin canonical rings of log stacky curves

Aaron Landesman, Peter Ruhm, Robin Zhang

Consider modular forms arising from a finite-area quotient of the upper-half plane by a Fuchsian group. By the classical results of Kodaira-Spencer, this ring of modular forms may…

math.NT2025

A positive Siegel theorem: Dynkin friezes and positive Mordell-Schinzel

Robin Zhang

We determine the number of positive integral points on -dimensional affine varieties associated to arbitrary generalized Cartan matrices. An application to the theo…

math.NT2023

The Harris-Venkatesh conjecture for derived Hecke operators I: imaginary dihedral forms

Robin Zhang

The Harris-Venkatesh conjecture posits a relationship between the action of derived Hecke operators on weight-one modular forms and Stark units. We prove the full Harris-Venkatesh…

math.NT2024

The Harris-Venkatesh conjecture for derived Hecke operators II: a unified Stark conjecture

Robin Zhang

We prove a compatibility theorem between the Stark conjecture and the Harris-Venkatesh conjecture for imaginary dihedral modular forms of weight . The key technical input is a g…

math.RT2026

Corrigendum to "Modular Gelfand pairs and multiplicity-free representations"

Patrick Allen, Preston Wake, Robin Zhang

Some of the multiplicity-freeness results in ``Modular Gelfand pairs and multiplicity-free representations'' are stated in overly broad generality. We provide counterexamples and p…

math.NT2025

Uniform bounds on periodic points of polynomials with good reduction

Isaac Rajagopal, Robin Zhang

We establish effective bounds on the number of periodic points of degree- polynomials defined over -adic fields and number fields, under a mild reduction hypothesis that…

math.NT2015

On quadratic periodic points of quadratic polynomials

Zhiming Wang, Robin Zhang

Bounding the number of preperiodic points of quadratic polynomials with rational coefficients is one case of the Uniform Boundedness Conjecture in arithmetic dynamics. Here, we pro…

math.NT2024

The conjecture, uniform boundedness, and dynamical systems

Robin Zhang

We survey Vojta's higher-dimensional generalizations of the conjecture and Szpiro's conjecture as well as recent developments that apply them to various problems in arithmeti…

math.CO2026

On maximal Dynkin friezes

Robin Zhang

The maximal entries of Dynkin friezes over the positive integers have recently been determined for all finite Dynkin types except and . In this note, we explicitly const…

math.NT2024

The Harris-Venkatesh conjecture for derived Hecke operators III: local constants

Robin Zhang

The first two papers in this series prove the Harris-Venkatesh conjecture and its refinement with the Stark conjecture for imaginary dihedral modular forms of weight . This pape…

cs.LG2026

Humanity's Last Exam

Long Phan, Alice Gatti, Ziwen Han +1144

Benchmarks are important tools for tracking the rapid advancements in large language model (LLM) capabilities. However, benchmarks are not keeping pace in difficulty: LLMs now achi…

math.RT2023

Modular Gelfand pairs and multiplicity-free representations

Robin Zhang

We give a generalization of Gelfand's criterion on the commutativity of Hecke algebras for Gelfand pairs and multiplicity-free triples over algebraically closed fields of arbitrary…

math.NT2025

Towards the -adic derived Hecke algebra for weight one forms

Robin Zhang

This note outlines an approach to defining -adic Shimura classes and -adic derived Hecke operators on the completed cohomology of modular curves from upcoming work by the aut…

math.GR2022

Grupos ortogonales sobre cuerpos de característica positiva

Robin Zhang

This exposition examines the theory of orthogonal groups and their subgroups over fields of positive characteristic, which has recently been used as an important tool in the study…