On commuting integer matrices

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Chapman, Jonathan, Mudgal, Akshat
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908332116148224
author Chapman, Jonathan
Mudgal, Akshat
author_facet Chapman, Jonathan
Mudgal, Akshat
contents Given $d, N \in \mathbb{N}$, we define $\mathfrak{C}_d(N)$ to be the number of pairs of $d\times d$ matrices $A,B$ with entries in $[-N,N] \cap \mathbb{Z}$ such that $AB = BA$. We prove that $$ N^{10} \ll \mathfrak{C}_3(N) \ll N^{10},$$ thus confirming a speculation of Browning-Sawin-Wang. We further establish that $$ \mathfrak{C}_2(N) = K(2N+1)^5 (1 + o(1)),$$ where $K>0$ is an explicit constant. Our methods are completely elementary and rely on upper bounds of the correct order for restricted divisor correlations with high uniformity.
format Preprint
id arxiv_https___arxiv_org_abs_2504_15839
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle On commuting integer matrices
Chapman, Jonathan
Mudgal, Akshat
Number Theory
Combinatorics
11D45 (Primary), 15A27, 15B36 (Secondary)
Given $d, N \in \mathbb{N}$, we define $\mathfrak{C}_d(N)$ to be the number of pairs of $d\times d$ matrices $A,B$ with entries in $[-N,N] \cap \mathbb{Z}$ such that $AB = BA$. We prove that $$ N^{10} \ll \mathfrak{C}_3(N) \ll N^{10},$$ thus confirming a speculation of Browning-Sawin-Wang. We further establish that $$ \mathfrak{C}_2(N) = K(2N+1)^5 (1 + o(1)),$$ where $K>0$ is an explicit constant. Our methods are completely elementary and rely on upper bounds of the correct order for restricted divisor correlations with high uniformity.
title On commuting integer matrices
topic Number Theory
Combinatorics
11D45 (Primary), 15A27, 15B36 (Secondary)
url https://arxiv.org/abs/2504.15839