Title
A Spectral Assignment Approach For The Graph Isomorphism Problem
Abstract
In this paper, we propose algorithms for the graph isomorphism (GI) problem that are based on the eigendecompositions of the adjacency matrices. The eigenvalues of isomorphic graphs are identical. However, two graphs G(A) and G(B) can be isospectral but non-isomorphic. We first construct a GI testing algorithm for friendly graphs and then extend it to unambiguous graphs. We show that isomorphisms can be detected by solving a linear assignment problem (LAP). If the graphs possess repeated eigenvalues, which typically correspond to graph symmetries, finding isomorphisms is much harder. By repeatedly perturbing the adjacency matrices and by using properties of eigenpolytopes, it is possible to break symmetries of the graphs and iteratively assign vertices of G(A) to vertices of G(B), provided that an admissible assignment exists. This heuristic approach can be used to construct a permutation which transforms G(A) into G(B) if the graphs are isomorphic. The methods will be illustrated with several guiding examples.
Year
DOI
Venue
2014
10.1093/imaiai/iay001
INFORMATION AND INFERENCE-A JOURNAL OF THE IMA
Keywords
DocType
Volume
graph isomorphism problem, friendly graphs, linear assignment problem
Journal
7
Issue
ISSN
Citations 
4
2049-8764
1
PageRank 
References 
Authors
0.36
9
2
Name
Order
Citations
PageRank
Stefan Klus1176.09
Tuhin Sahai2112.54