In 2012, Nobel Prize-winning scientist Frank Wilczek proposed the existence of a new type of crystal. While most crystals have a structure that repeats in two or three dimensions, Wilczek imagined a crystal that repeated in four: the three dimensions of space as well as one dimension of time. He called these hypothetical crystals ‘time crystals,’ and just last year scientists finally figured out how to create them in a lab.
Now, a reveal that time crystals don’t only exist as products in a lab. They can also form in all kinds of other situations, and that creating a time crystal is much easier than scientists previously believed. This could have ramifications for groups looking to use time crystals to build new atomic clocks, gyroscopes, or for other applications.
Time crystals behave in strange ways when they’re hit with electromagnetic waves. In a time crystal, the molecules all spin in a certain direction, and they switch direction at every pulse of electromagnetic waves. But even if the pulses are uneven, the crystals still switch direction at regular intervals, meaning they could be used as a form of keeping time.
Last year, researchers figured out how to create time crystals in a lab for the first time, using a complicated method involving a precision laser and a collection of ytterbium atoms. But this shows that time crystals can form much easier, and the method is simple enough that a child can do it.
The researchers discovered time crystals forming inside normal crystals made of monoammonium phosphate, which is a common ingredient in crystal growing kits. Theoretically, there could be time crystals inside every crystal grown by children as a science project.
“Our work suggests that the signature of a [time crystal] could be found, in principle, by looking in a children's crystal growing kit,” said study author Sean Barrett.
This is good news for people working on time crystals because this means that such crystals are easier to obtain. Exactly how they form so easily is still an open question, however, which shows just how much we still have to learn about these enigmatic structures.