Simple Relations Behind Complex Systems
Scaling relations widely exist in complex systems. Kleiber’s law described an empirical $\frac{3}{4}$ factor of metabolic scaling. The WBE theory then verified a series of biological scaling relations, including the Kleiber’s law. In 2007, Bettencourt et al. discovered that similar scaling relations also widely exist in cities, while Bettencourt alone then gave a more general scaling model for urban regions of varying structures.