We study combinatorial indicators related to the characteristic phase transitions associated with the optimization problems of coloring the nodes of a graph with the minimum number of colors and of finding an independent set of maximum cardinality in a graph. In particular, we investigate the...

We study network growth from a fixed set of initially isolated nodes placed at random on the surface of a sphere. The growth mechanism we use adds edges to the network depending on strictly local gain and cost criteria. Only nodes that are not too far apart on the sphere may be considered for...

We study directed random graphs (random graphs whose edges are directed) as they evolve in discrete time by the addition of nodes and edges. For two distinct evolution strategies, one that forces the graph to a condition of near acyclicity at all times and another that allows the appearance of...