John Hopfield, Ph.D. ’58, won the 2024 Nobel Prize in Physics. Hopfield, a Professor Emeritus at Princeton shares the award with Geoffrey Hinton from the University of Toronto.

The two were honored for their work training artificial neural networks; As the Nobel organization said in the announcement, they “leveraged tools from physics to develop methods that form the basis of today’s powerful machine learning.”

Hopfield in particular was cited for inventing one network of the same namebased on principles of physics “that can store and reconstruct images and other types of patterns in data.”

Hinton – who used Hopfield’s network as the basis for another network, known as the Boltzmann machine – and Hopfield will share the cash prize of 11 million Swedish kronor (about $1 million).

As Princeton reportedHopfield learned of the award when he returned to the thatched cottage where he lives in England: “My wife and I went out to get our flu shot and stopped to get a coffee on the way home.” he said, noting that they came back to find an “amazing” and “heartwarming” collection of emailed congratulations.

A graduate of Swarthmore University, Hopfield studied at Cornell under the theoretical physicist Albert Overhauser, who later won the National Medal of Science.

“He (Overhauser) gave me enormous support as a listener and critic when I visited him, but finding orientation and solving technical-theoretical problems was entirely my problem,” Hopfield recalled in a 2018 essay, in where he reflected on his life and career. “The great gift he gave me was responsibility for an interesting question and full responsibility for research and progress.”

Hopfield’s long career included work at Bell Labs and the California Institute of Technology, as well as more than 25 years at Princeton.

His many awards and honors include a MacArthur Genius Grant, the Benjamin Franklin Medal in Physics, and the Albert Einstein World Award of Science from the World Cultural Council.

“For me – I grew up with a father and mother who were both physicists – physics was not a subject. The atom, the troposphere, the nucleus, a piece of glass, the washing machine, my bicycle, the phonograph, a magnet—all were incidentally the subject,” Hopfield wrote in the 2018 essay.

“The central idea was that the world is understandable, that one should be able to take everything apart, understand the relationships between its parts, carry out experiments and, on that basis, be able to develop a quantitative understanding of its behavior . Physics held that with effort, ingenuity, and adequate resources, the world around us can be understood in a predictable and reasonably quantitative way. Being a physicist is a dedication to the search for this kind of understanding.”

Beth Saulnier is editor-in-chief of Cornellians.