Combinatorics Seminar
Professor Saieed Akbari
Sharif University of Technology & IPM
c-Sum Flows in Graphs
Abstract: Let G be a graph. For a real number c, a c-sum flow of G is an assignment of non-zero real numbers to the edges of G such
that the sum of values of all edges incident with each vertex is c. Let k be a natural number. A c-sum k-flow is a
c-sum flow whose absolute values from the set {1,...,k}. In this talk, we present known results on c-sum k-flows of graphs
and propose several conjectures.
The four-color theorem states that any map in a plane can be colored using
four-colors in such a way that regions sharing a common boundary (other than
a single point) do not share the same color. Nowhere-zero
flows in directed graphs are important because they have nice relations with four color theorem.
Here, we provide a bridge between nowhere-zero flows in directed graphs and 0-sum flows in undirected graphs.
Monday July 28, 2014 at 3:00 PM in SEO 427