A mysterious phase of matter has unlocked crucial clues about our universe right now. But what about the past and future?

If you’ve ever watched Doctor Who, you know—and love—TARDIS, the sentient, police box-shaped spacecraft that enables the titular time lord to travel through space and time. In Doctor Who lore, TARDIS is powered by time crystals, those exotic artifacts portrayed elsewhere in science fiction as the ultimate tools for zigzagging across dimensions. But sci-fi, of course, has repeatedly proven to be the precursor of real-life science, which begs the question: Could time crystals actually help us visit the past and future?

Physicists at the University of Maryland made the first time crystal using a one-dimensional chain of ytterbium ions.

Chris Monroe, University of Maryland