Contrarian Majority Rule Model with External Oscillating Propaganda and Individual Inertias.

GIMENEZ, M.C.; REINAUDI, LUIS; GALAM, SERGE; VAZQUEZ, FEDERICO

ENTROPY

MOLECULAR DIVERSITY PRESERVATION INTERNATIONAL-MDPI

Lugar: Basel; Año: 2023

1099-4300

We study the Galam majority rule dynamics with contrarian behavior and an oscillatingexternal propaganda in a population of agents that can adopt one of two possible opinions. Inan iteration step, a random agent interacts with three other random agents and takes the majorityopinion among the agents with probability p ( t ) (majority behavior) or the opposite opinion withprobability 1 − p ( t ) (contrarian behavior). The probability of following the majority rule p ( t ) varieswith the temperature T and is coupled to a time-dependent oscillating field that mimics a mass media propaganda, in a way that agents are more likely to adopt the majority opinion when it is aligned with the sign of the field. We investigate the dynamics of this model on a complete graph and find various regimes as T is varied. A transition temperature T c separates a bimodal oscillatory regime for T < T c , where the population’s mean opinion m oscillates around a positive or a negative value from a unimodal oscillatory regime for T > T c in which m oscillates around zero. These regimes are characterized by the distribution of residence times that exhibit a unique peak for a resonance temperature T ∗ , where the response of the system is maximum. An insight into these results is given by a mean-field approach, which also shows that T ∗ and T c are closely related.