Opinion evolution in the Sznajd model on interdependent chains

Most previous works study the evolution of opinions by commonly employing an isolated single network. However, this is not fully consistent with recent identification that interaction between networks plays a crucial rule in the dynamical behaviors taking place on them. In this work, we consider a system including two chains with the same size, entangled with each other by the introduction of probabilistic interconnections and communication. We introduce the Sznajd model into such system and study how the coupling effect influences the evolution of opinions of the whole system. Simulation results show that strong interaction and communication between two interdependent chains promote the whole system to achieve consensus easily. Interestingly, we find that with the increase of connection probability, the time evolutions of magnetization of the two chains are gradually consistent and there exists an intermediate region of intercommunication probability leading to the shortest exit time. In addition, the exit time depends on the numbers of Ising spins in a power-law form. The consensus of one chain can change the critical behavior of the other even with a small connection or communication probability.