English

Skew-symmetric matrices and their principal minors

Combinatorics 2015-05-27 v2

Abstract

Let VV be a nonempty finite set and A=(aij)i,jVA=(a_{ij})_{i,j\in V} be a matrix with entries in a field K\mathbb{K}. For a subset XX of VV, we denote by A[X]A[X] the submatrix of AA having row and column indices in XX. We study the following problem. Given a positive integer kk, what is the relationship between two matrices A=(aij)i,jVA=(a_{ij})_{i,j\in V}, B=(bij)i,jVB=(b_{ij})_{i,j\in V} with entries in K\mathbb{K} and such that det(A[X])=det(B[X])\det(A\left[ X\right])=\det(B\left[ X\right]) for any subset XX of VV of size at most kk ? The Theorem that we get in this Note is an improvement of a result of R. Loewy [5] for skew-symmetric matrices whose all off-diagonal entries are nonzero.

Keywords

Cite

@article{arxiv.1403.0095,
  title  = {Skew-symmetric matrices and their principal minors},
  author = {A. Boussairi and B. Chergui},
  journal= {arXiv preprint arXiv:1403.0095},
  year   = {2015}
}