Graphical designs and extremal combinatorics

Autor: Konstantin Golubev
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Linear Algebra and its Applications, 604
ISSN: 0024-3795
1873-1856
DOI: 10.3929/ethz-b-000428111
Popis: A graphical design is a proper subset of vertices of a graph on which many eigenfunctions of the Laplacian operator have mean value zero. In this paper, we show that extremal independent sets make extremal graphical designs, that is, a design on which the maximum possible number of eigenfunctions have mean value zero. We then provide examples of such graphs and sets, which arise naturally in extremal combinatorics. We also show that sets which realize the isoperimetric constant of a graph make extremal graphical designs, and provide examples for them as well. We investigate the behavior of graphical designs under the operation of weak graph product. In addition, we present a family of extremal graphical designs for the hypercube graph.
Linear Algebra and its Applications, 604
ISSN:0024-3795
ISSN:1873-1856
Databáze: OpenAIRE