Professor Maxi San Miguel, Institute for Cross-Disciplinary Physics and Complex Systems, University of the Balearic Islands, Mallorca, Spain

Abstract: Studies of cultural differentiation have shown that social mechanisms that normally lead to cultural globalization - homophily and influence - can also explain how distinct cultural groups (polarization) can form. So long as the level of heterogeneity in the population is high enough, cultural diversity can emerge. However, this emergent cultural diversity has proven to be unstable in the face of "cultural drift" - small errors or innovations that allow cultures to change from within. A model of cultural differentiation that combines the traditional mechanisms of homophily and influence with a third mechanism of "network homophily" is proposed. In this model network structure co-evolves with cultural interaction so that social ties are allowed to change with cultural influence. This results in a fragmentation of the social network leading to patterns of cultural diversity that are stable in the presence of cultural drift.