A graph G is uniquelyembeddable in a surface f 2 if for any two embeddings f,,f2 : G + f 2 , there exists an isomorphism u : G + G and a homeo- admits an embedding f : G + F2 such that for any isomorphism (T : G + G, there is a homeomorphism h : F 2 f 2 with h . f = f . u. It will be shown that if
An algebraic characterization of projective-planar graphs
β Scribed by Lowell Abrams; Daniel C. Slilaty
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 114 KB
- Volume
- 42
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
We give a detailed algebraic characterization of when a graph G can be imbedded in the projective plane. The characterization is in terms of the existence of a dual graph G* on the same edge set as G, which satisfies algebraic conditions inspired by homology groups and intersection products in homology groups. Β© 2003 Wiley Periodicals, Inc. J Graph Theory 42: 320β331, 2003
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