Detecting deepfakes, in a world where even reality is suspect

Hany Farid, a leading expert on deepfakes and digital manipulation, estimates that half of the content widely viewed on the Internet is fake. What does this mean for our ability to detect images generated or hallucinated by artificial intelligence?

Last February, a Tomahawk cruise missile struck an Iranian elementary school, killing more than 150 people, most of them children. President Trump initially suggested that it could have been somebody else's Tomahawk: "Whether it's Iran or somebody else, the fact that a Tomahawk – a Tomahawk is very generic, it's sold to other countries, but that's being investigated right now," he said.When Iran put out video as evidence that it was a U.S. missile, Hany Farid, one of the world's foremost experts on deepfakes, was contacted by several media outlets to determine if it was real or fake.A professor at Dartmouth College, Farid is also co-founder of GetReal Security, a cyber security firm.

"What was difficult about this case was you had very little to work on," he said. "We had a very grainy, shaky video. The missile is extremely small. And we had to reason about the physical plausibility of that missile striking the ground."But he also had certain aspects that he could study scientifically, involving the speed of sound, the speed of light, and the size of the missile: "And those three things were enough for us to say that this is physically plausible," he said. "And this is the important part: all evidence led us to the belief that the video was authentic, and there's been no