Published in
Elsevier, Linear Algebra and its Applications, 1-3(283), p. 75-85, 1998
DOI: 10.1016/s0024-3795(98)10082-4
Links
Tools
On graphs with multiple eigenvalues
Journal article published in 1998 by
Peter Rowlinson
This paper is made freely available by the publisher.
Full text: Download
Published version:
archiving forbidden
Data provided by 
Abstract
Let (μ) be an eigenspace of a finite graph G, with dimension m and codimension t >1. It is shown that if μ ∉ {−1, 0} then . A necessary and sufficient condition for μ to be a multiple eigenvalue of G is established, and used to construct examples from intersecting families of sets.