Photo of Leo P. Kadanoff

Leo P. Kadanoff

  • National Medal of Science
  • Physical Sciences

For fundamental theoretical research in the areas of statistical, solid state and nonlinear physics and, in particular, for the development of scaling techniques in these fields.

In physics, when boiling water turns to steam, a “second-order phase transition” has occurred. During the 1960s, scientists researched the mathematical principles behind the metamorphosis of matter.

To explain these phenomena, Leo P. Kadanoff used another transition, ferromagnetism, whereby atoms in magnets rearrange themselves to produce a magnetic field.

As temperature increases, he concluded, atoms become jumbled in a fractal-like pattern, and the magnetic field begins to disappear. Through this research, Kadanoff’s major contribution was the introduction of “scaling” and “universality.” Scaling demonstrates similarities in behavior of matter across a range of scales – from microscopic particles to objects of everyday life.

Meanwhile, universality involves the discovery of similar paths taken by different substances as they’re undergoing a phase transition. Later, Kadanoff also contributed to chaos theory, the study of complex, unpredictable systems.

Today, the center for theoretical physics at the University of Chicago bears Kadanoff’s name, mimicking his dream of bringing different scientists together to solve problems.