Memory and Personality Shape Ideological Polarization

Abstract: We do experiments on physical agents with dynamic binary ideologies, deep memories of previous probes of neigboring agents, but fixed personalities that interpret the memory content to make ideological decisions. We find experimentally a critical memory depth below which complete ideological polarization of the collective cannot occur, and above which it is inevitable, an emergent symmetry breaking that is memory depth dependent. Depending on the details of the personalities, the polarization can be static or dynamic in time, even in certain cases chaotic due to nonreciprocity in how the agents respond to other agents. Thus, agents with different personalities and depths of memory serve as a physics analog of the ideology dynamics among biased individuals, illuminating how decisions influenced by individual memories of past interactions can shape and influence subsequent polarization. Perhaps such applications of physics-based systems to political systems will help us to understand the ideological instabilities observed today.