From Puppies to Pendulums

When a group of thirsty puppies competes for a bowl of milk, each tries to gain the biggest share. Each puppy’s objective is simple and clear. So how is it possible that they end up huddling close to each other and moving in a pinwheel?

The study of how simple rules can lead to complex emergent phenomena—such as thirsty puppies creating pinwheels—fascinates Marshall Kuypers, Co-President of the Stanford Complexity Group (SCG). “Surprisingly many phenomena, ranging from ant colony behavior to price bubbles in economics, can be explained from this viewpoint,” Marshall says.

This field of study, also known as complex systems, has a rich history spanning multiple disciplines. The Nobel Laureate and philosopher Friedrich Hayek dedicated much of his work in the 1950s-70s to the study of complex phenomena in psychology and biology. In the 1940s mathematicians and information scientists such as Norbert Wiener and John von Neumann observed complex systems at play in cybernetics research.

“A very nice example involving agent-based models is the work of Thomas Schelling, who won the Nobel Prize in Economics in 2005,” explains Marshall. While investigating racial segregation in populations, what Schelling found was that the geographical segregation came about from each individual expressing just a very slight preference for living near people of the same ethnicity.

Despite its ubiquity, it was only in recent decades that complex systems emerged as an independent field, with the establishment of institutions such as the Santa Fe Institute and the New England Complex Systems Institute as well as journals like Complex Systems.

“When I applied for a PhD program in the US, universities told me that if you want a PhD in complex systems you can start by applying to an economics or biology graduate program. There was no stand-alone program for such an interdisciplinary field,” says Marshall.

“It’s weird.”

According to Marshall, the “weird,” interdisciplinary nature of complex systems is one key reason why it has not reached out to as many intellectual communities as it should. More needs to be done to spread the ideas of complex systems. “This is one of our goals at the Stanford Complexity Group.”

UntitledThe SCG, founded in 2009, was originally created to serve a small body of faculty and graduate students interested in the field. Today, it is run by a team of PhD students whose diverse interests range from population biology to modern thought and literature. “All of us [in the SCG] are fascinated by how complex systems thinking relates to our intellectual or research pursuits,” Marshall says. Marshall himself has worked on agent-based models in economics, applying mathematical tools from network theory to investigate emergent properties in consumer-producer markets.

The SCG, Marshall elaborates, invites speakers from around the world to give talks on campus. It also offers an introductory seminar on complex systems every Winter Quarter, and makes three-minute video clips that communicate important ideas about complex systems in an accessible manner.

“The double pendulum is a standard example of a complex physical system. But if you Google it, you wouldn’t be able to find a nice video explaining how it works,” explains Marshall. So the team at SCG decided to make one, with the help of a local artist. The video about the double pendulum can be found on the SCG website.

Apart from reaching out to the Stanford community and communicating complex systems to the public, the SCG has a larger vision of becoming the Bay Area hub for complex systems. “New Mexico has Santa Fe, the East Coast has the New England Complex Systems Institute. There’s also one in the Midwest. Where are the West Coast’s complex systems theorists?” quips Marshall.

For Marshall, complex systems is as under-noticed as it is emerging. Much is waiting to be discovered. Marshall, who also works at the Center for International Security and Cooperation (CISAC) and is pursuing a PhD with the Department of Management Science and Engineering (MS&E), hopes to find ways to marry his interest in complex systems with his current research on risk analysis.

“There seems to be little interaction between my current PhD work and my interest in complex systems that led me to pursue my PhD in the first place. But it’s worth thinking about the potential connections that a relatively new field like complex systems could have.”


by Alan Aw