Computing’s prestigious Turing Award went to two men who created a way of keeping digital communication safe even in the age of quantum computers.
Modern encryption relies on computers’ inability to unpick calculations involving enormous prime numbers, but quantum computers will sidestep that problem.
“Quantum cryptography,” proposed by Charles Bennett and Gilles Brassard in the 1980s, relies on a quirk of subatomic physics: That observing a particle changes it. The technique encodes the code’s “key” in individual photons, so if that key is intercepted, the sender and recipient will know.
When Bennett and Brassard designed the technique, it was clever but largely useless; now, as quantum computing looms, governments and Big Tech are actively pursuing it to keep their data safe.