English

Is This a New Class of Matrices?

Rings and Algebras 2023-09-19 v1

Abstract

We consider a new class of matrices associated to a real square matrix AA and to a vector c{1,1}n\vec{c} \in \{-1,1\}^n such that c1=1c_1=1 by using a map φc\varphi_{\vec{c}} which turns out to be a conjugation of a matrix AA by a signature matrix. It is shown that every such matrix is similar and congruent to a matrix AA and that they have same permanental polynomials. There are 2n12^{n-1} maps φc\varphi_{\vec{c}} and they form an abelian group under the composition of maps isomorphic to the group (Z2n1,+)({\mathbb{Z}_2}^{n-1}, +). A decomposition of matrices, on a symmetric and antisymmetric matrix under a map φc\varphi_{\vec{c}}, is considered. Particularly, it is shown that sum of all principal minors of the order two of a matrix AA is equal to the sum of all principal minors of the order two of their symmetric and antisymmetric parts. It is shown that any symmetric matrix and any antisymmetric matrix under the map φc\varphi_{\vec{c}} are simultaneously permutation similar to certain block matrices which have two blocks. Finally, for a fixed matrix AA, it is proved that the number of different matrices φc(A)\varphi_{\vec{c}}(A) is 2nt2^{n-t}, where tt is the number of connected components of the graph GG whose adjacency matrix is AA.

Keywords

Cite

@article{arxiv.2309.08933,
  title  = {Is This a New Class of Matrices?},
  author = {Jovan Mikić},
  journal= {arXiv preprint arXiv:2309.08933},
  year   = {2023}
}
R2 v1 2026-06-28T12:23:28.735Z