[Resource Topic] 2024/1156: On affine forestry over integral domains and families of deep Jordan-Gauss graphs

Welcome to the resource topic for 2024/1156

Title:
On affine forestry over integral domains and families of deep Jordan-Gauss graphs

Authors: Tymoteusz Chojecki, Grahame Erskine, James Tuite, Vasyl Ustimenko

Abstract:

Let K be a commutative ring. We refer to a connected bipartite graph G = G_n(K) with partition sets P = K^n (points) and L = K^n (lines) as an affine graph over K of dimension dim(G) = n if the neighbourhood of each vertex is isomorphic to K. We refer to G as an algebraic affine graph over K if the incidence between a point (x_1, x_2, . . . , x_n)
and line [y_1, y_2, . . . , y_n] is defined via a system of polynomial equations of the kind f_i = 0 where f_i ∈ K[x_1, x_2, . . . , x_n, y_1, y_2, . . . , y_n]. We say that an affine algebraic graph is a Jordan-Gauss graph over K if the incidences between points and lines are given by a
quadratic system of polynomial equations, and the neighbourhood of each vertex is given as a solution set of the system of linear equations in row-echelon form.
For each integral domain K we consider the known explicit construction of the family of Jordan-Gauss graphs A(n, K), n = 2, 3, . . . with cycle indicator ≥ 2n + 2. Additionally several constructions of families of edge intransitive Jordan-Gauss graphs over K of
increasing girth with well defined projective limit will be presented. This projective limit is a forest defined by the system of algebraic equations. In the case K = F_q, q ≥ 3 we present results of computer experiments for the evaluation of girth, cycle indicator, diameter and the second largest eigenvalue of the constructed graphs, and we formulate
several conjectures on their properties. One of the conjectures is that the girth of A(n, F_q) is 2[(n+ 5)/2]. We discuss briefly some applications of Jordan-Gauss graphs of large girth to Graph Theory, Algebraic Geometry and the theory of LDPC codes; and we consider ideas to use groups related to these graphs in Noncommutative Cryptography and Stream Ciphers Design.

ePrint: https://eprint.iacr.org/2024/1156

See all topics related to this paper.

Feel free to post resources that are related to this paper below.

Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.

For more information, see the rules for Resource Topics .