A pair of AI scientists won the Nobel Prize in physics on Tuesday for foundational discoveries and inventions that enable machine learning with artificial neural networks.

John J. Hopfield, a professor at Princeton University, and Geoffrey E. Hinton, a professor at the University of Toronto, used tools from physics to develop methods that became the foundation of today’s powerful machine learning, the Nobel Foundation said.

“When we talk about artificial intelligence, we often mean machine learning using artificial neural networks. This technology was originally inspired by the structure of the brain,” the foundation said. “This year’s laureates have conducted important work with artificial neural networks from the 1980s onward.”

Hopfield created a model that can store and retrieve patterns such as images, based on principles from physics.

Hinton expanded on Hopfield’s work by developing the so-called Boltzmann machine. Using tools from statistical physics, he invented a method that can autonomously find properties in data, so it can perform tasks such as identifying specific elements in pictures. His work helped start the current explosive development of machine learning.

These breakthroughs are now widely applied across many fields, including materials science, where they help develop new materials with specific properties.

Hinton told a news conference that he is both excited about the role he has played in the explosion of AI technologies but also worried about “possible bad consequences.”

“It will mean huge improvements in productivity but we also have to worry about a number of possible bad consequences, particularly the threat of these things getting out of control,” he said.

He also said he uses OpenAI’s GPT-4 a lot, but he added a word of caution.

“I don’t totally trust it because it can hallucinate,” he said.

The 2023 physics prize was awarded to Pierre Agostini, Ferenc Krausz and Anne L’Huillier for their work on creating extremely short pulses of light, a discovery that has enabled scientists to study the rapid movements of electrons inside atoms and molecules.

On Monday, two U.S. scientists won this year’s medical Nobel for their discovery of microRNA and its role in post-transcriptional gene regulation.

Nobel announcements continue this week with the chemistry award on Wednesday, the literature award on Thursday and the peace prize on Friday. The Nobel for economic sciences will be announced on Monday, closing out this year’s awards.