MIT's Wilczek Wins 2004 Nobel Prize in Physics

(Originally published by the Massachusetts Institute of Technology)

October 6, 2004

Professor Frank Wilczek, MIT's Herman Feshbach Professor of Physics, has won the 2004 Nobel Prize in physics for a "colorful" discovery in the world of quarks, the building blocks of the atomic nucleus.

The work, which involves the dominant, or "color," force between quarks, is key to several major problems in particle physics and beyond. Wilczek, 53, shares the prize of about $1.3 million with David J. Gross of the University of California at Santa Barbara, and H. David Politzer of the California Institute of Technology.

Wilczek was in the shower when the call from Sweden came at 5:30 a.m. Tuesday morning. "It was this person with a beautiful accent, and it was so early, so I was immediately hopeful," said Wilczek's wife, Betsy Devine. "Frank came in, dripped all over the floor, and talked to half the Swedish Academy."

The three won "for the discovery of asymptotic freedom in the theory of the strong interaction," according to the Royal Swedish Academy of Sciences.

Asymptotic freedom is a phenomenon whereby quarks behave as free particles when they are close together, but become more strongly attracted to each other as the distance between them increases. This theory forms the key to the interpretation of almost all experimental studies involving modern particle accelerators.

"Thanks to their discovery, David Gross, David Politzer and Frank Wilczek have brought physics one step closer to fulfilling a grand dream, to formulate a unified theory comprising gravity as well -- a theory for everything," the Academy said in announcing the prize.

"What this year's laureates discovered was something that, at first sight, seemed completely contradictory. The interpretation of their mathematical result was that the closer the quarks are to each other, the weaker is the 'colour charge.' When the quarks are really close to each other, the force is so weak that they behave almost as free particles.

"The converse is true when the quarks move apart: the force becomes stronger when the distance increases. This property may be compared to a rubber band. The more the band is stretched, the stronger the force.

"This discovery was expressed in 1973 in an elegant mathematical framework that led to a completely new theory, Quantum ChromoDynamics, QCD. This theory was an important contribution to the Standard Model, the theory that describes all physics connected with the electromagnetic force (which acts between charged particles), the weak force (which is important for the sun's energy production) and the strong force (which acts between quarks). With the aid of QCD physicists can at last explain why quarks only behave as free particles at extremely high energies. In the proton and the neutron they always occur in triplets," said the Academy.

Wilczek's earliest work, done with Gross at Princeton in the 1970s, concerned the change of fundamental couplings with energy. This work led to the discovery of asymptotic freedom, which makes it possible to understand the behavior of matter under extreme conditions, such as occurred in the earliest moments of the Big Bang. Also, it permits the construction of unified models of particle interactions, which have concrete predictive power.

Wilczek has been a leading participant in all these developments. One notable result of the cosmological work is a compelling explanation of the asymmetry between matter and antimatter in the present universe.

In the past few years, another concept Wilczek discovered and developed, fractional quantum statistics, has been found to characterize the behavior of recently discovered states of matter. It is the focal point of much current activity in condensed matter physics.

Wilczek's many awards include the the 2002 Lorentz Medal from the Royal Netherlands Academy of Arts and Sciences, which called him "one of the most influential theoretical physicists of his generation." He is a member of the American National Academy of Sciences, and has received the Dirac Medal (1994) and the Michelson-Morley Prize (2002).

Wilczek was born in Queens, N.Y. He received his B.S. (1970) from the University of Chicago and his M.A. (1971) and Ph.D. (1973) from Princeton University. He later became professor of physics at Princeton and at the University of California at Santa Barbara.

He joined the MIT faculty in 2000 with appointments in the Department of Physics and the Center for Theoretical Physics. This year he was named one of five Kavli Scholars through MIT's Center for Space Research, soon to be renamed the Kavli Institute for Astrophysics and Space Research. "We love MIT," Devine said in a telephone interview. "It's been wonderful for Frank and our family."

Wilczek regularly speaks and writes on theoretical physics for a wide audience.

He and his wife live in Cambridge, Mass. They have two daughters, Amity and Mira. Amity, who has a Ph.D. from Harvard, is currently a postdoctoral associate in biology there. Mira, who earned her S.B. from MIT in 2004, works for IBM in Boston.