Abstract
We give a combinatorial characterization of graphs whose normalized Laplacian has three distinct eigenvalues. Strongly regular graphs and complete bipartite graphs are examples of such graphs, but we also construct more exotic families of examples from conference graphs, projective planes, and certain quasi-symmetric designs.
| Original language | English |
|---|---|
| Pages (from-to) | 2560-2569 |
| Journal | Linear Algebra and its Applications |
| Volume | 435 |
| Issue number | 10 |
| Publication status | Published - 2011 |