Rapisarda, Andrea; Stefan Thurner and Constantino Tsallis (Guest Editors)
Complexity and complex systems emerge in natural, artificial, and social contexts, and have attracted strong and enthusiastic scientific attention all over the world during the last decades. The study of these fascinating systems focuses on concepts of emergent behavior, living organisms, languages, earthquakes, economics, ecology, social networks, and other fundamental problems of contemporary science and societies. Most of these systems are out-of-equilibrium and present weak chaos, long-range correlations, nonergodic behavior, multifractal hierarchical structures, for which standard equilibrium Boltzmann-Gibbs statistical mechanics is not applicable. In the last few decades, a large variety of complex systems, in various fields, has been successfully described using nonextensive generalized formalisms of statistical mechanics.