Faculty of Science

2013 Nerenberg Lecture with Leo Kadanoff: From Complexity to Curricula

By Mitch Zimmer

Something as simple as a brook flowing around a rock can reveal complex patterns of eddies and chaotic swirls within a water stream. Leo Kadanoff is a pioneer
Turbulent flow of fluid around an object

Complex turbulent flow.

in analysing how such complexity can emerge from fundamental origins and how multiple complexities within a system can form machines spontaneously. However, as soon as the 2013 Nerenberg Lecturer introduced these concepts he took an interlude to comment on the controversial topic of Intelligent Design (ID) and its influence in the United States. Kadanoff pointed out that proponents of ID argue that biological systems are too complex to have been a product of natural evolution but are result of shaping and forming through an intelligent creator.  One of these people is Michael Behe of Lehigh University, a biochemist who had done work on sickle cell anemia and a senior fellow of the Discovery Institute's Center for Science and Culture. Kadanoff made references to him throughout the talk.

The political context of ID is a reality through the Discovery Institute who have a adopted a “Wedge Strategy” that “seeks nothing less that the overthrow of materialism and its cultural legacies” which will result in “the integration of design theory into public school science curricula.” Kadanoff proposes that academics should consider the validity of the Intelligent Design arguments with an “open but critical mind.”

Kadanoff returned to the main theme of the talk saying that the structure of physics is based on a few simple ideas.  That the same basic laws of physics hold everywhere and always and expressible in terms of mathematics. “Everything is simple and neat- except, of course, the world.” He then asked “why is the world so complicated?”  Here, Kadanoff stated that there are different types of complexity.  Type 1 complexity has structures with variations in size shape placement; think of the repeating eddies and swirls in the brook. Type 2 complexity is where many different structures work together, all for an apparent purpose as found in a biological cell.

Intricacy may also be involved as seen in gene regulation, which controls the functioning and development of the organism. As Kadanoff said, “We certainly would wish to explain how they become so complex.”

Kadanoff notes that complexity is different from chaos in that many different variations come apparent and that it is hard to predict which will come out in a given place and time.

The world is both complex and chaotic. It is here where Kadanoff raises of ID’s objection to evolution.  “Behe argues that biological objects, cells in particular, are too complex to have arisen from any natural process.  They are composed of many working parts and each part is necessary for the organism to function. How could so many parts evolve independently?  Since he cannot imagine any natural process which might have produced them, Behe argues that such a complex outcome requires a creator or Creator.”

Kadanof demonstrating plumes

Dr. Kadanoff describing the structure of plumes.

Kadanoff contends that Behe’s argument is mostly theoretical as it depends on the strength of his imagination. “Let’s be more real. Let’s look and see how complexity actually arises in our world, in particular fluid flow.”  To demonstrate this, Kadonoff showed a diagram of a transparent box filled with water that is heated from the bottom and cooled from the top.  At first, as the temperature difference is increased, motion swirls develop since the cool water at the top of the device becomes denser and sinks down. Conversely, the heated water at the bottom of the box becomes less dense and it floats to the top.   Soon the water starts cycling within the box. If the temperature is increased the cycle breaks down and the swirls become non-repeating.  When the temperature is increased further a different pattern emerges where an overall rotating motion of independently moving structures called plumes appear.   These plumes are shaped like mushrooms or jellyfish and yet as they pass by thermometers they produce chaotic readings. Even though there are equations to describe all fluid flows, they do not directly reveal what is happening in this interesting complex situation. Plumes are examples of emergent objects that arise spontaneously from the water to become part of a complex machine. These flowing liquids organize themselves to produce complexity with many different working parts each serving a different function. Kadanoff then said that Behe “cannot imagine how a thing as complex as a living cell might have been produced.  In physics we often see things that are far beyond our initial imagination and expectation.”

Kadanoff then showed a computer model of fluid motion based on four basic rules. A fluid contains many particles in motion; particles and momentum are conserved, they are never lost but only move around; momentum moves with the particles and lastly; the technical requirements must be accounted for.  If the above are done right, a model of fluid behaviour can be constructed to imitate what happens in the real world. Using vector diagrams to represent the momentum direction and that occurs in each cell of a matrix, a complex flow pattern emerged on its own. “For this complexity, no intelligent creator is necessary. Simple events, linked together and repeated sufficiently often can produce complex outcomes.”

Kadanoff then pondered. “What if these patterns themselves rearranged into superstructures,...Such piling of complexity upon complexity could work to produce the richness of biological systems.” Kadanoff stated that there isn’t much known about how complexity arises either in living beings or in early biological forms and he does give credit to people like Behe to point out the gaps, but the Intelligent Design community do not seem to have anything positive to add to the discussion.

Kadanoff then ended the lecture with a few notes about school curricula. “We should not let the particular view of the universe provided by the followers on Intelligent Design to replace science in the school curricula. Instead we should notice that evolutionary biology, paleontology and cosmology are not speculations. They are root parts of science and human knowledge. They belong in schools as part of the basics of our curriculum and of our understanding of the materials world.  Other subjects, unrooted in experiment, should be avoided in school science classrooms.”

Kadonff receiving Nerenberg ceritificate

Dr. Bryan Neff (left) presnting the 2013 Nerenberg Lecture certificate to Dr. Leo Kadanoff