Abstract

We show that if G=(V,E) is a 4-connected flat graph, then any real symmetric V×V matrix M with exactly one negative eigenvalue and satisfying, for any two distinct vertices i and j, Mij<0 if i and j are adjacent, and Mij=0 if i and j are nonadjacent, has the Strong Arnold Property: there is no nonzero real symmetric V×V matrix X with MX=0 and Xij=0 whenever i and j are equal or adjacent. (A graph G is flat if it can be embedded injectively in 3-dimensional Euclidean space such that the image of any circuit is the boundary of some disk disjoint from the image of the remainder of the graph.)This applies to the Colin de Verdière graph parameter, and extends similar results for 2-connected outerplanar graphs and 3-connected planar graphs.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.