Thermodynamics of Complex Systems

Abstract

Complex systems use flows of energy to keep existing functions going while still having enough reserves to learn, grow, develop, and heal. In this chapter, thermodynamics is introduced as the study of energy flows. The basic ideas of energy, entropy, work, phase transitions, and the laws of thermodynamics are introduced through intuitive examples. These concepts are expanded beyond the usual heat-specific formulations to include any kind of gradient that might drive flows and perform work. An emphasis is placed on Gibbs’ formulation that makes a distinction between total energy and the energy available for work. The problem of precisely defining order and disorder in complex systems is also addressed. A major component of the chapter is how complex systems are often energetically open to their environment. Metabolism is discussed as a general principle whereby high-quality energy enters the system, is used to perform work, and then exits the system as lower-quality energy. In this context, dissipative and far from equilibrium systems are discussed. The possibility of doing work on the environment is considered, but then turned inward to explore how a system might become a structurally adaptive system that can heal, learn, and grow. A proposal is also made for the kinds of basic functions that seem to evolve inside of complex systems. Applications come from traffic flow, ecosystems, autocatalytic reactions, and business and political systems. More provocative issues taken up are what it might mean for a system to be alive and the nature of a mind. The chapter concludes with questions for either reflection or group discussion as well as resources for further exploration.