Skew-symmetric matrices and their principal minors
arXiv:1403.0095
Abstract
Let be a nonempty finite set and be a matrix with entries in a field . For a subset of , we denote by the submatrix of having row and column indices in . We study the following problem. Given a positive integer , what is the relationship between two matrices , with entries in and such that for any subset of of size at most ? 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.