Source Of Complexity (An Introduction to Complex Systems in Environment)

Mezemate Yacine, Schertzer Daniel

We saw in the previous lesson some complex systems that can be found in environment. We also highlighted that there is non single definition of complexity. Through this lesson we will focus on the sources of complexity in a given system, what are the issues that can arise for the best model a complex system such as: at what scale should we describe the behaviors of the system's components?. What are the scales involved in the evolution of the system?. We can list some characteristics of complex systems: Too many components, too many constraints, too many parameters for consideration to accomplish a particular task. Not enough information about essential elements or components of a system or about their interfaces. Not enough information about how elements or components will behave under known or unknown conditions that may lead to unintended consequences Among the sources of complexity we will focus on the non-linearity of complex systems and differential equations which describe them. We will show that some methods of analysis based on scale invariance can be considered as good candidates for the characterization of complex systems. Second module of the course set "An Introduction to Complex Systems in Environment"