Complexity is a matter of distance

Complex systems constitute a cross-disciplinary field that studies natural and societal phenomena. In general, complexity relates to different aspects of a system, such as emergent behaviours, interaction patterns, and other properties. Also, complexity can refer to the resources required to accomplish a task. Here, we review a limited collection of methods for studying complexity across different topics. The resulting picture highlights interesting relationships between complexity and distance, showing up in all considered systems, from phase transitions to black hole evolution. We conclude by discussing related implications and a few examples beyond Physics that corroborate the validity of the highlighted relationships. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

Complex systems study natural and societal phenomena, involving emergent behaviors, interaction patterns, and resource requirements. This review examines methods for studying complexity across various topics, revealing interesting relationships between complexity and distance in different systems, from phase transitions to black hole evolution. Implications and examples beyond Physics further support the validity of these relationships.