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Negative results on characterizing visibility graphs

✍ Scribed by H. Everett; D. Corneil


Publisher
Elsevier Science
Year
1995
Tongue
English
Weight
860 KB
Volume
5
Category
Article
ISSN
0925-7721

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✦ Synopsis


There is no known combinatorial characterization of the visibility graphs of simple polygons. In this paper we show negative results on two different approaches to finding such a characterization. We show that Ghosh's three necessary conditions for a graph to be a visibility graph are not sufficient thus disproving his conjecture. We also show that there is no finite set of minimal forbidden induced subgraphs that characterize visibility graphs.


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