Time Crystal News
A space-time crystal or four-dimensional crystal is a theoretical structure periodic in time and space. It extends the idea of a crystal to four dimensions. The idea was proposed by Frank Wilczek in 2012. His speculation was that a construct would have a group of particles that move and periodically return to their original state, perhaps moving in a circle, and form a time crystal. In order for this perpetual motion to work, the system must not radiate its rotational energy. This type of motion is distinct from that of persistent currents in a superconductor, wherein the rotating Cooper pair...