“For the first time ever, we kind of have a time-traveling machine going in both directions,” said Sonja Franke-Arnold, a quantum physicist at the University of Glasgow in Scotland who was not involved in the research.

Regrettably for science fiction fans, the devices have nothing in common with a 1982 DeLorean. Throughout the experiments, which were conducted by two independent teams in China and Austria, laboratory clocks continued to tick steadily forward. Only the photons flitting through the circuitry experienced temporal shenanigans. And even for the photons, researchers debate whether the flipping of time’s arrow is real or simulated.

Scientists have discovered how to reverse time inside a quantum system. From a teenager taking a stylish Delorean 88 miles per hour to two-hearted alien creatures flying a blue police box, our fiction has been filled with fun stories about time travel. However, it looks like time travel is now no longer a matter of science fiction but science fact.

In the physical world, time marches in one direction, but things aren’t so straight forward in the quantum realm. Researchers have discovered that it’s possible to speed up, slow down, or reverse the flow of time in a quantum system. This isn’t exactly time travel, but is instead implementing or reverting to different quantum states from different points in time.