Perimeter Institute extends its sincerest condolences to the family, friends, and colleagues of physicist Leo Kadanoff , who died this week at 78.

A professor emeritus of physics at the University of Chicago and a Distinguished Visiting Research Chair at Perimeter Institute since 2009, Kadanoff was regarded as a founder of modern statistical physics and theoretical condensed matter physics.

“Leo was one of the greats of 20th century physics,” said Perimeter Institute Director Neil Turok . “He was a polymath, a pioneer, yet as down-to-Earth as one could possibly be. In spite of all the great work he had done, he had such humility and such love of sharing: a fresh mind, always working on something original. He will be sorely missed by us all.”

Kadanoff was a lecturer for the first three years of Perimeter Scholars International (PSI) , beginning with the 2009 launch of the graduate program, and he thrived on mentoring curious young physicists. He was also among the first group of Perimeter’s Distinguished Visiting Research Chairs , enabling him to spend a number of weeks or months at the Institute each year to focus on research and collaboration.

Kadanoff made foundational contributions to quantum field theory, particularly our modern understanding of renormalization, and he co-authored a prominent textbook on quantum statistical mechanics. He was a beloved teacher – he earned the University of Chicago’s Quantrell Award for excellence in teaching – and a past president of the American Physical Society.