Scientists have broken a fundamental law of physics by creating a “time crystal” for the first time ever using a chain of ions.

Scientists at the University of Maryland and the University of California-Berkeley have successfully created crystals that repeat in time instead of a spatial pattern, which were previously thought of to be non-existent.

Researchers at the two universities created a ring-shaped quantum system of ytterbium ions, which behave like particles with spin that can point either up or down.

While a standard crystal repeats in a regular spatial pattern, a time crystal repeats in time, returning to a similar configuration at regular intervals.

By using a laser physicists flipped the spins in a chain of ions halfway around, which allowed the ions to interact in a way where the spin of each ion would influence the others. They then repeated this sequence at regular intervals, flipped the ions and let them interact. After measuring the results, scientists discovered that the ions on average went full circle and returned to their original states in twice the time interval at which they were flipped halfway.

The scientists found that the ions spins returned to their original orientation at the same rate even if they were not flipped perfectly halfway, which indicates that the system of ions prefers to respond at a regular time period in a similar manner that atoms in a crystal prefer to respond in a perfectly spaced lattice.

This breakthrough is particularly important because spontaneous symmetry breaking is a fundamental concept in many areas of physics, according to the study.

Frank Wilczek, a theoretical physicist from MIT, proposed the possibility of time crystals in 2012, which has been previously deemed impossible by most physicists.