Inverse eigenvalue problem for Laplacian matrices of a graph

Shaun Fallat, Himanshu Gupta, Jephian C. -H. Lin

Published 2024-11-01Version 1

For a given graph $G$, we aim to determine the possible realizable spectra for a generalized (or sometimes referred to as a weighted) Laplacian matrix associated with $G$. This specialized inverse eigenvalue problem is considered for certain families of graphs and graphs on a small number of vertices. Related considerations include studying the possible ordered multiplicity lists associated with stars and complete graphs and graphs with a few vertices. Finally, we investigate the both theoretically and numerically, the minimum variance over a family of generalized Laplacian matrices with a size-normalized weighting.