# Interacting and Multi-type Networks

**When:**Wednesday, February 20, 2013 at 3:00 pm

**Where:**DA 114

**Speaker**: Elizabeth A. Leicht

**Organization**: Senior Research Fellow, Said Business School, University of Oxford

**Sponsor**: Physics Colloquium

Networks are widely used as concise mathematical representations of systems of interacting components. The approach often taken is to treat a system of interest as a single network possessing only one type of node and one type of edge. In reality, many systems of interacting components are more accurately described as networks of networks or networks with multiple types of nodes and edges. For instance, modern critical infrastructure has dependencies spanning assorted electric grids, telecom and computer networks, and transportation networks; likewise, the global financial crisis of 2007-2008 revealed the extent to which some relatively new financial products created unrealized interconnectivity among financial intermediaries leading to significant negative consequences. In this talk I will present a random graph model of interacting networks. Within this model I will show that network interactions can lower the critical threshold for the onset of large-scale network connectivity and stabilize cascades.