Physicists have made a crystal of time that we can really see

Of all the eccentricities in the quantum kingdom, time crystals – atomic arrangements that repeat certain movements over time – can be among the strangest. But they certainly exist, and to provide more solid proof, physicists have finally created a crystal of time that we can really see.

In a recent article of nature materials, physicists from the University of Colorado Boulder presented a new design of time crystals: a glass cell filled with liquid crystals – rod -shaped molecules stuck in strange limbo between solid and liquid. This is the same thing that we find in LCD screens for smartphone. When struck with light, crystals shake and dance in repetitive models which, according to the researchers, resemble “psychedelic tiger stripes”.

“They can be observed directly under the microscope and even, under special conditions, by the naked eye,” said Hanqing Zhao, the main study and a graduate student at the University of Colorado Boulder, in a press release. Technically, these crystalline dances can last hours, such as a “clock eternally turned”, added the researchers.

Asymmetrical curiosity

Time Crystals appeared for the first time in a 2012 article by Nobel Laureat Frank Wilczek, who presented an idea for an impossible crystal which breaks several rules of symmetry in physics. More specifically, a crystal of time breaks symmetry because its atoms do not lock themselves in a continuous network and their positions change over time.

Physicists have since demonstrated versions of Wilczek’s proposal, but these crystals lasted a terribly short time and were microscopic. Zhao and Ivan Smalyukh, the main author of the study and physicist at the University of Colorado Boulder, wanted to see if they could overcome these limits.

Find the molecular “fold”

For the new crystal of time, the duo exploited the “folds” of the molecules – their tendency to regroup when it was tight in a certain way. Once together, these folds behave like whole atoms, the researchers explained.

“You have these twists and turns, and you cannot easily delete them,” said Smalyukh. “They behave like particles and begin to interact with each other.”

The team has coated two glass cells with coloring molecules, sandwiching a liquid crystal solution between the layers. When they flashed the configuration with a polarized light, the coloring molecules turned inside the glass, tightening the liquid crystal. This formed thousands of new folds inside the crystal, explained the researchers.

“It is the beauty of this crystal era,” said Slyukh. “You just create conditions that are not so special. You make a light shine, and everything occurs.”

The team believes that its iteration of time that Crystal could have practical uses. For example, a “time watermark” printed on invoices could be used to identify counterfeits. In addition, stacked layers could serve as a tiny data center.

It is rare that quantum systems are visible to the naked eye. Only time will tell us if this time the crystal represents anything – the researchers “do not want to put a limit to the applications at the moment” – but even if it is not the case, it is always a neat demonstration of the way in which physical theories exist in strange and unexpected corners of reality.