Circular bidiagonal pairs
Abstract
A square matrix is said to be circular bidiagonal whenever (i) each nonzero entry is on the diagonal, or the subdiagonal, or in the top-right corner; (ii) each subdiagonal entry is nonzero, and the entry in the top-right corner is nonzero. Let denote a field, and let denote a nonzero finite-dimensional vector space over . We consider an ordered pair of -linear maps and that satisfy the following two conditions: (i) there exists a basis for with respect to which the matrix representing is circular bidiagonal and the matrix representing is diagonal; (ii) there exists a basis for with respect to which the matrix representing is circular bidiagonal and the matrix representing is diagonal. We call such a pair a circular bidiagonal pair on . We classify the circular bidiagonal pairs up to affine equivalence. There are two infinite families of solutions, which we describe in detail.
Keywords
Cite
@article{arxiv.2301.00121,
title = {Circular bidiagonal pairs},
author = {Paul Terwilliger and Arjana Žitnik},
journal= {arXiv preprint arXiv:2301.00121},
year = {2024}
}
Comments
30 pages