{ "id": "2307.04741", "version": "v1", "published": "2023-07-10T17:52:32.000Z", "updated": "2023-07-10T17:52:32.000Z", "title": "Cohen-Lenstra distribution for sparse matrices with determinantal biasing", "authors": [ "András Mészáros" ], "categories": [ "math.PR", "math.CO" ], "abstract": "Let us consider the following matrix $B_n$. The columns of $B_n$ are indexed with $[n]=\\{1,2,\\dots,n\\}$ and the rows are indexed with $[n]^3$. The row corresponding to $(x_1,x_2,x_3)\\in [n]^3$ is given by $\\sum_{i=1}^3 e_{x_i}$, where $e_1,e_2,\\dots,e_n$ is the standard basis of $\\mathbb{R}^{[n]}$. Let $A_n$ be random $n\\times n$ submatrix of $B_n$, where the probability that we choose a submatrix $C$ is proportional to $|\\det(C)|^2$. Let $p\\ge 5$ be a prime. We prove that the asymptotic distribution of the $p$-Sylow subgroup of the cokernel of $A_n$ is given by the Cohen-Lenstra heuristics. Our result is motivated by the conjecture that the first homology group of a random two dimensional hypertree is also Cohen-Lenstra distributed.", "revisions": [ { "version": "v1", "updated": "2023-07-10T17:52:32.000Z" } ], "analyses": { "keywords": [ "sparse matrices", "cohen-lenstra distribution", "determinantal biasing", "first homology group", "dimensional hypertree" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }