Seeing with radio Wi-Fi-like equipment can see people through walls, measure their heart rates, and gauge emotions

WHEN I WAS A BOY, I secretly hoped I would discover latent within me some amazing superpower—say, X-ray vision or the ability to read people's minds. Lots of kids have such dreams. But even my fertile young brain couldn't imagine that one day I would help transform such superpowers into reality. Nor could I conceive of the possibility that I would demonstrate these abilities to the president of the United States. And yet two decades later, that's exactly what happened.