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Time Crystals
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Using Crystals To Bend Time

By James Donahue

Of all the substances of the earth, crystals are among the strangest. While they look like rocks, crystals do strange things like . . . for instance . . . change color and if watched closely over time, and under certain conditions, they grow. Yet most scientists refuse to consider that they are living creatures.

Now Nobel Prize-winning physicist Frank Wilczek, in his intense study of the atomic structure of crystals, has made a discovery that he believes may make perpetual motion possible, and consequently challenge all theories of everything we think we know and understand about time.

As Wilczek explained: "I was thinking about the classification of crystals, and then it just occurred to me that it’s natural to think about space and time together. So if you think about crystals in space, it’s very natural also to think about the classification of crystalline behavior in time."

When matter crystallizes, its atoms organize themselves into the rows, columns and stacks of a three-dimensional lattice. Each atom occupies a "lattice point" but the balance of forces between the atoms prevents them from moving into the space in between.

But crystals do not behave like other matter. Wilczek noted that they "break the spatial symmetry of nature" and for them, "the usual role that all places in space are equivalent" does not seem to apply. Thus he said "crystals derive their movement not from stored energy but from a break in the symmetry of time, enabling a special form of perpetual motion."

While working on this problem, Wilczek came up with mathematical equations that indicate that all atoms could form a regularly repeating lattice in time, breaking time symmetry for brief moments before returning to their initial place.

Now a team of scientists has joined Wilczek in designing and building a "perpetuum mobile," or "time crystal" that will test the idea by generating an endless supply of energy. If it works, they will not only have created a perpetual motion machine, but perhaps achieved a better understanding of time.

The physicists working on this, led by Xiang Zhang, a nanoengineer at Berkeley and Tongcang Li, a physicist and postdoctoral researcher under Zhang, are attempting to create a time crystal in the form of a constantly rotating ring of charged atoms, or ions. They are calling it an "ion trap." It is expected to take the team at least three years or longer to complete this project.

A story by Natalie Wolchover for Simons Science News gives us some insight into the intricacies of this project, and what the team is attempting to accomplish. She wrote:

"Electric fields will be used to corral calcium ions into a 100-micron-wide ‘trap,’ where they will form a crystalline ring. The scientists believe a static magnetic field will cause the ring to rotate."

Understanding just how tiny this device will be is explained by noting that the trap, at just 100-microns, is about the width of a human hair. Within this field, the team "must precisely calibrate the electrodes to smooth out the field. Because like charges repel, the ions will space themselves evenly around the outer edge of the trap, forming a crystalline ring," Wolchover wrote.

"At first, the ions will vibrate in an excited state, but diode lasers like those found in DVD players will be used to gradually scatter away their extra kinetic energy. According to the group’s calculations, the ion ring should settle into its ground state when the ions are laser-cooled to around one-billionth of a degree above absolute zero. The technology for accomplishing this has only recently become available.

Once this is accomplished, Wolchover said researchers will switch on a static magnetic field within the trap. If their hypothesis is correct, this should "induce the ions to start rotating (and continue doing so indefinitely.)"

Writer Jacob Sloan, in a review for Disinformation, wrote: "The hope is that time crystals will push physics beyond the precise but seemingly imperfect laws of quantum mechanics and lead the way to a grander theory. If time crystals are able to break time symmetry in the same way that conventional crystals break space symmetry, it tells you that in nature those two quantities seem to have similar properties, and that ultimately should reflect itself in a theory."