Time in a bottle
“It’s no longer just a wild theory. Two independent teams of physicists have followed a recipe to build the world’s first versions of an enigmatic form of matter – time crystals.
MIT physicist and Nobel laureate Frank speculated about the existence of time crystals in 2012, while teaching a class on ordinary crystals, such as salt, or snowflakes. In a typical crystal, the atoms or molecules are tightly arranged in regularly repeating patterns in three-dimensional space, resembling a lattice.
Wilczek thought it might be possible to create a similar crystal-like structure in time, which is treated as a fourth dimension under relativity. Instead of regularly repeating rows of atoms, a time crystal would exhibit regularly repeating motion.
Many physicists were sceptical, arguing that a time crystal whose atoms could loop forever, with no need for extra energy, would be tantamount to a perpetual motion machine – forbidden by the laws of physics.
Wilczek countered that a time crystal was more akin to a superconductor in which electrons flow with no resistance, and in theory could do so forever without the need to add energy to the system. In a time crystal, electrons would travel in a loop rather than a line and occasionally bunch up rather than flow smoothly, repeating in time the way atoms in ordinary crystals repeat in space.
Now, in a paper published this week, Norman Yao at the University of California, Berkeley, and his colleagues have revealed a blueprint for making a time crystal. The recipe has already been followed by two teams…”