Uniform Kirchhoff graphs

Autor: Tyler M. Reese, Joseph D. Fehribach, Brigitte Servatius, Randy Paffenroth
Rok vydání: 2019
Předmět:
Zdroj: Linear Algebra and its Applications. 566:1-16
ISSN: 0024-3795
DOI: 10.1016/j.laa.2018.12.018
Popis: This paper presents an entirely linear-algebraic interpretation of Kirchhoff graphs. Specifically, whether or not a vector graph is Kirchhoff can be determined using only the incidence matrix of the underlying digraph, and the characteristic matrix of the vector assignment function. This is then used to classify the families of matrices for which any Kirchhoff graph must be uniform, in the sense that the vector edges all occur the same number of times. Next, we demonstrate that any matrix having a Kirchhoff graph must always have a uniform example. Finally, we introduce a notion of 2-connectedness of vector graphs, and show that every 2-connected Kirchhoff graph must be uniform.
Databáze: OpenAIRE