Wednesday, March 15, 2017
Bizarre forms of matter called time crystals were supposed to be physically impossible - PHYSICS
Bizarre forms of matter called time crystals were supposed to be physically impossible. Now they’re not
Time crystals are hypothetical structures that pulse without requiring any energy—like a ticking clock that never needs winding. The pattern repeats in time in much the same way that the atoms of a crystal repeat in space. The idea was so challenging that when Nobel prizewinning physicist Frank Wilczek proposed the provocative concept in 2012, other researchers quickly proved there was no way to create time crystals.
But there was a loophole—and researchers in a separate branch of physics found a way to exploit the gap. Monroe, a physicist at the University of Maryland in College Park, and his team used chains of atoms they had constructed for other purposes to make a version of a time crystal. “I would say it sort of fell in our laps,” says Monroe.
And a group led by researchers at Harvard University in Cambridge, Massachusetts, independently fashioned time crystals out of 'dirty' diamonds. Both versions, which are published in Nature, are considered time crystals, but not how Wilczek originally imagined. “It's less weird than the first idea, but it's still fricking weird,” says Norman Yao, a physicist at the University of California, Berkeley, and an author on both papers.
They are also the first examples of a remarkable type of matter—a collection of quantum particles that constantly changes, and never reaches a steady state. These systems draw stability from random interactions that would normally disrupt other kinds of matter.
Interesting reading via SA:https://www.scientificamerican.com/article/the-quest-to-crystallize-time/