Spectral characterizations of the Lovász number and the Delsarte number of a graph
Spectral characterizations of two closely related graph functions are given: the Lovász number (the theta function) \(\vartheta \) and a generalization \(\vartheta^1\) of Delsarte's linear programming bound. These characterizations involve the largest eigenvalue of a type of weighted Laplacian that \textit{F. R. K. Chung} introduced in her book [Spectral graph theory (Regional Conference Series in Mathematics. 92, Providence, RI: American Mathematical Society) (1997; Zbl 0867.05046)].
scientific article; zbMATH DE number 1553308