Speaker: Isaac McMullin, recent PhD graduate of Dalhousie University

Date & time: Wednesday, October 7, 3.40pm.

Location: Chase 227 at Dalhousie University or online via ZOOM

Abstract:

There are many ways we can model the robustness of a network to random failure. A common method involves all vertices being operational and each edge independently failing with probability q. The all-terminal reliability polynomial of a graph G is the probability in q that the spanning subgraph of operational edges is connected. Similarly, given a directed graph (or digraph) D with a specified vertex v and each arc failing with probability q, the reachability polynomial is the probability in q that in the spanning subgraph of operational arcs there is a directed path from v to every other vertex in the graph. In this talk we discuss the many similarities between reliability and reachability. Despite that, however, they differ in interesting ways. For example, while the complex roots for reliability are not known to have modulus greater than 1.2, the closure of the complex reachability roots is the entire complex plane.

Organizer: Jeannette Janssen Jeannette.Janssen@Dal.Ca

Zoom link:
https://us02web.zoom.us/j/88013261876?pwd=XGocyHqvseXY8metPztPoSuulEEejX.1