The Nobel Prize in Physics has been awarded to two scientists, Geoffrey Hinton and John Hopfield, for their work on machine learning.

British-Canadian Professor Hinton is sometimes referred to as the “Godfather of AI” and said he was flabbergasted.

He resigned from Google in 2023, and has warned about the dangers of machines that could outsmart humans.

The announcement was made by the Royal Swedish Academy of Sciences at a press conference in Stockholm, Sweden.

American Professor John Hopfield, 91, is a professor at Princeton University in the US, and Prof Hinton, 76, is a professor at University of Toronto in Canada.

Machine learning is key to artificial intelligence as it develops how a computer can train itself to generate information.

It drives a vast range of technology that we use today from how we search the internet to editing photographs on our phones.

“I had no idea this would happen. I’m very surprised,” said Prof Hinton, speaking on the phone to the Academy minutes after the announcement.

He said he was in a hotel with bad internet in California and thought he might need to cancel the rest of his day’s plans.

The Academy listed some of the crucial applications of the two scientists’ work, including improving climate modelling, development of solar cells, and analysis of medical images.

Prof Hinton’s pioneering research on neural networks paved the way for current AI systems like ChatGPT.

In artificial intelligence, neural networks are systems that are similar to the human brain in the way they learn and process information. They enable AIs to learn from experience, as a person would. This is called deep learning.

Prof Hinton said his work on artificial neural networks was revolutionary.

“It’s going to be like the Industrial Revolution – but instead of our physical capabilities, it’s going to exceed our intellectual capabilities,” he said.

But he said he also had concerns about the future. He was asked if he regretted his life’s work as he told journalist last year.

In reply, he said he would do the same work again, “but I worry that the overall consequences of this might be systems that are more intelligent than us that might eventually take control”.

He also said he uses the AI chatbot ChatGPT4 for many things now but with the knowledge that it does not always get the answer right.

Professor John Hopfield invented a network that can save and recreate patterns.

It uses physics that describes a material’s characteristics due to atomic spin.

In a similar way to how the brain tries to recall words by using associated but incomplete words, Prof Hopfield developed a network that can use incomplete patterns to find the most similar.

The Nobel Prize committee said the two scientists’ work has become part of our daily lives, including in facial recognition and language translation.

But Ellen Moons, chair of the Nobel Committee for Physics, said “its rapid development has also raised concerns about our future collectively”.

The winners share a prize fund worth 11m Swedish kronor (£810,000).

When Prof Hinton resigned from Google last year, he told the BBC some of the dangers of AI chatbots were “quite scary”.

He also said at the time that his age had played into his decision to leave the tech giant.

Earlier this year, in an interview with BBC Newsnight, he said the UK government will have to establish a universal basic income to deal with the impact of AI on inequality, as he was “very worried about AI taking lots of mundane jobs”.

He added that while AI would increase productivity and wealth, the money would go to the rich “and not the people whose jobs get lost and that’s going to be very bad for society”.

In the same interview, he said developments over the last year showed governments were unwilling to rein in military use of AI while the competition to develop products rapidly meant there was a risk tech companies wouldn’t “put enough effort into safety”.

Prof Hinton said “my guess is in between five and 20 years from now there’s a probability of half that we’ll have to confront the problem of AI trying to take over”.

• 2023 – Pierre Agostini, Ferenc Krausz and Anne L’Huillier for work on attoseconds – extremely short pulses of light that can be used to capture and study rapid processes inside atoms;

• 2022 – Alain Aspect, American John Clauser and Austrian Anton Zeilinger for research into quantum mechanics – the science that describes nature at the smallest scales;

• 2021 – Syukuro Manabe, Klaus Hasselmann and Giorgio Parisi were given the prize for advancing our understanding of complex systems, such as Earth’s climate;

• 2020 – Sir Roger Penrose, Reinhard Genzel and Andrea Ghez received the prize for their work on the nature of black holes;

• 2019 – James Peebles, Michel Mayor and Didier Queloz shared the prize for ground-breaking discoveries about the Universe;

• 2018 – Donna Strickland, Arthur Ashkin and Gerard Mourou were awarded the prize for their discoveries in the field of laser physics.