AI researchers fear undetectable fakes

Rishi Sunak is Britain's prime minister.

If some advertisements on Facebook can be trusted (which they cannot) he also appears to be flogging get-rich-quick schemes. One such advert shows Mr Sunak endorsing an app supposedly developed by Elon Musk, a businessman, into which viewers can make regular "savings".

The video is fake. Generated with the help of AI, it is just one of 143 such advertisements catalogued by Fenimore Harper Communications, a British firm, which ran in December and January. It is not just those in the public eye who can have their likenesses used for dubious ends. In June 2023 the Federal Bureau of Investigation in America warned the public of "malicious actors" using AI to create fake sexually themed videos and images of ordinary people, in order to extort money.

How to detect such trickery is a live topic among AI researchers, many of whom attended NeurIPS, one of the field's biggest conferences, held in New Orleans in December. A slew of firms, from startups to established tech giants such as Intel and Microsoft, offer software that aims to spot machine-generated media. The makers of big AI models, meanwhile, are searching for ways of "watermarking" their output so that real pictures, video or text can be readily distinguished from the machine-generated sort.

But such technologies have not, so far, proved reliable. The AI cognoscenti seem gloomy about their prospects. The Economist conducted a (deeply unscientific) straw poll of delegates to NeurIPS. Of 23 people asked, 17 thought Al-generated media would eventually become undetectable. Only one believed that reliable detection would be possible. (The other five demurred, preferring to wait and see.)