English

A note on the minimum skew rank of a graph

Combinatorics 2017-02-10 v1

Abstract

The minimum skew rank mr(F,G)mr^{-}(\mathbb{F},G) of a graph GG over a field F\mathbb{F} is the smallest possible rank among all skew symmetric matrices over F\mathbb{F}, whose (ii,jj)-entry (for iji\neq j) is nonzero whenever ijij is an edge in GG and is zero otherwise. We give some new properties of the minimum skew rank of a graph, including a characterization of the graphs GG with cut vertices over the infinite field F\mathbb{F} such that mr(F,G)=4mr^{-}(\mathbb{F},G)=4, determination of the minimum skew rank of kk-paths over a field F\mathbb{F}, and an extending of an existing result to show that mr(F,G)=2match(G)=MR(F,G)mr^{-}(\mathbb{F},G)=2match(G)=MR^{-}(\mathbb{F},G) for a connected graph GG with no even cycles and a field F\mathbb{F}, where match(G)match(G) is the matching number of GG, and MR(F,G)MR^{-}(\mathbb{F},G) is the largest possible rank among all skew symmetric matrices over F\mathbb{F}.

Keywords

Cite

@article{arxiv.1206.3409,
  title  = {A note on the minimum skew rank of a graph},
  author = {Yanna Wang and Bo Zhou},
  journal= {arXiv preprint arXiv:1206.3409},
  year   = {2017}
}