Summary: A Characterization of
Projective-Planar
Signed Graphs
Dan Archdeacon
Dept. of Math. and Stat.
University of Vermont
Burlington, VT, USA 05405
e-mail: dan.archdeacon@uvm.edu
Marisa Debowsky
Dept. of Math. and Stat.
University of Vermont
Burlington, VT, USA 05405
e-mail: marisa.debowsky@uvm.edu
June 5, 2001
Abstract
A signed graph has a plus or minus sign on each edge. A cycle is
balanced or unbalanced depending on whether it contains an even or
odd number of negative edges respectively. We consider embeddings
of a signed graph in the projective plane where a cycle is essential
if and only if it is unbalanced. We characterize those signed graphs

Source: Archdeacon, Dan - Department of Mathematics and Statistics, University of Vermont

Collections: Mathematics