They are dynamic, spatial and material arrays of buildings that are constructed, reworked and rebuilt over time, decaying, collapsing and expanding in irregular episodes of growth and incorporation. The hypothesis of this article is that the unification of these two approaches, combining the studies of flows through networks in relation to the physical forms of the city, and how each acts upon the other over time, will be a significant step towards understanding of the dynamics of cities. Cities are the largest and most complex material forms constructed by humans, but they are far more than an immensely extended artefact. Michael Weinstock, Director of Research and Development at the Architectural Association (AA) in London, proposes a mathematical approach to uncovering the dynamics of cities. He advocates a dual method that reveals any city’s particular metabolism by simultaneously mapping its physical shape – its compactness and densities – and its flows of energy, information and materials. Contemporary mathematical studies of cities that are derived from the historical development of the studies of metabolism in biology have been focused either on the ‘allometric’ 3 relations of the physical forms of the urban morphology such as the overall shape, compactness and density,
How might we best track the accelerating demands of global urbanisation? From this perspective, cities are not static arrays of material structures, but are regarded as analogous to living beings, as they consume energy, food, water and other materials, excrete wastes and maintain themselves down through the generations. The urbanisation of the world is accelerating, and it is thought that within less than two generations there will be an additional 2 billion urban dwellers, most of whom will be located in Southeast Asia, China, India and Africa.2
The expansion of existing cities and the creation of new cities to meet this demand is a daunting task. or on the relations of energy, information and material flows and their networks4 with the spatial patterns of the city. As the world population continues to grow, existing cities are expanding and new cities are being built, connected and integrated into the world system.

Updated: 31.10.2014 — 04:02