FQxI's Charles Bennett, a physicist at IBM Research, has been awarded the 2025 ACM A.M. Turing Award alongside Gilles Brassard of the Université de Montréal, for their foundational contributions to quantum information science (ACM award page).
Back in 1984, while the rest of the world was busy with Macintoshes and Ghostbusters, Bennett and Brassard were busy proving something: that you could use quantum mechanics to build encryption that's unbreakable. Not "really hard to break." Unbreakable. Their BB84 protocol showed that the security of a secret key could be guaranteed by physics itself, not by hoping your adversary doesn't have a big enough computer.
The work drew on ideas from their late collaborator Stephen Wiesner, and it largely invented quantum information science as a field. A lot of quantum computing efforts happening today trace a line back to what these two figured out over four decades ago. "Bennett and Brassard fundamentally changed our understanding of information itself," said Yannis Ioannidis, President of ACM (ACM press release).
Now, we're biased here. Charles Bennett is an FQxI member and has been part of our community for a number of years. His work on the relationship between physics and information is exactly the kind of foundational thinking that FQxI exists to support. So, we're allowed to be a little smug about this!
Watch Bennett's talk from the FQxI international conference in Banff: Occam's Razor, Wigner's Friend, and Boltzmann's Brain.
Congratulations to Charles and Gilles.
Image credits: Charles Bennett: IBM Research, CC BY-SA 2.0, via Wikimedia Commons. Gilles Brassard: Lëa-Kim Châteauneuf, CC BY-SA 4.0, via Wikimedia Commons.