Artificial intelligence is increasingly pervasive and capable but is also very hungry for power. Researchers, including those at the University of Tokyo, have developed a new approach to building physics-based AI—systems that use the natural behavior of physical systems to process information—that dramatically reduces the amount of computation required for them to run. The approach simplifies both how these systems learn and how they are structured. It was demonstrated using an optical computing system that processes information with light and could help pave the way toward faster and more energy-efficient AI hardware.