Jiazhen Liu, Shengda Huang, Nathan Aden, Neil Johnson, Chaoming Song
Polarization is a ubiquitous phenomenon in social systems. Empirical studies show substantial evidence for opinion polarization across social media. Recent modeling works show qualitatively that polarization emerges in coevolving networks by integrating reinforcing mechanisms and network evolution. However, a quantitative and comprehensive theoretical framework capturing generic mechanisms governing polarization remains unaddressed. In this paper, we discover a universal scaling law for opinion distributions, characterized by a set of scaling exponents. These exponents classify social systems into polarization and depolarization phases. We find two generic mechanisms governing the polarization dynamics, and propose a coevolving framework that counts for opinion dynamics and network evolution simultaneously. We show analytically three different phases including polarization, partial polarization, and depolarization, and the corresponding phase diagram. In the polarized phase, our theory predicts that a bi-polarized community structure emerges naturally from the coevolving dynamics. These theoretical…