ABSTRACT
This chapter considers the sustainability of the urban environment in terms of complex systems and non-equilibrium thermodynamics. It argues that the city is simultaneously an emergent phenomenon, triggered by persons building social relationships on a larger scale, and a place where other emergent phenomena take place. The chapter explores the new global geography based on physical, thermodynamic and economic indicators for the quality of energy flows crossing urban boundaries, so as to indicate and reinforce those flows that contribute to the development of the city, rather than to its growth. It assumes that the city is a complex urban ecosystem, the growth of which is sustained by the flows. The chapter explains various objects with multiple relationships and degrees of freedom, orientated towards a series of shared objectives, essentially the continuation and development of the city itself. Cities are physical systems in contact with various sources and sinks and energy flow from sources permeate the urban environment.
