This weekend I walked into a gallery on 21st street and saw this sculpture:
This photo captures the components of the system, but not the dynamics of it. Basically, you're looking at two fans facing each other and connected by four pieces of fishing line. Around the fishing line are wrapped two circular streamers of magnetic tape.
This is fundamentally a simple system - the fans provide continuous input - but the outcome is unbelievably complex. The two streamers bounce back and forth between the two fans. At time they appear to stand still and then wildly gyrate in a new direction. At no time can you predict where they are going to go next, nor do they ever take the same path twice.
This art installation is a fantastic visual example of what is talked about in a recent paper, The (Unfortunate) Complexity of the Economy, by Jean-Phillipe Bouchaud. Bouchaud shreds the notion that our economy can be explained simply by supply and demand. Instead, he outlines how many of the behaviours we see in our economy (bubbles, markets that never settle on an equilibrium, etc.) can be explained by different physical analogues. For example, the fans above are an example of a system that is incredibly sensible to the slightest perturbation in its environment, meaning that is constantly and dramatically changing state (sound like the stock market of late '08/early '09?). What's more, the system above is also governed by few simple actions (fans blow a tape wrapped around strings) yet incredibly complex action resuls (think about many people buying/selling a stock, yet prices gyrate madly).
If you read one academic paper this year, make it this one.