Nobel Prize-winning physicist (and “Nature of Reality” blogger) Frank Wilczek has gone public with a new and (some would say) radical idea—”time crystals.” They are, he says, hypothetical structures that move in recurring patterns without expending energy or slowing down. You could also call them perpetual motion machines, thought to be impossible according to the second law of thermodynamics. But Wilczek’s time crystals are slightly different since they don’t rely on energy. Instead, they stay in motion due to a “break in the symmetry of time.”
Here’s Natalie Wolchoer, writing for Simons Science News:
Wilczek’s idea met with a muted response from physicists. Here was a brilliant professor known for developing exotic theories that later entered the mainstream, including the existence of particles called axions and anyons, and discovering a property of nuclear forces known as asymptotic freedom (for which he shared the Nobel Prize in physics in 2004). But perpetual motion, deemed impossible by the fundamental laws of physics, was hard to swallow. Did the work constitute a major breakthrough or faulty logic? Jakub Zakrzewski, a professor of physics and head of atomic optics at Jagiellonian University in Poland who wrote a perspective on the research that accompanied Wilczek’s publication, says: “I simply don’t know.”
Now, a technological advance has made it possible for physicists to test the idea. They plan to build a time crystal, not in the hope that this perpetuum mobile will generate an endless supply of energy (as inventors have striven in vain to do for more than a thousand years) but that it will yield a better theory of time itself.
You can read more of about time crystals by following the link above, and you can check out Wilczek’s excellent blog posts for NOVA at “The Nature of Reality.”