When the researchers turned their tube of captured antimatter vertically, they found that the atoms moving downward along the magnetic field lines sped up thanks to the added pull of gravity; the atoms moving upward slowed down, also thanks to gravity trying to pull them Earthward. Anderson and her colleagues couldn’t actually watch the anti-atoms in action, of course, but their instruments counted the tiny flashes of energy every time an anti-hydrogen atom, pulled downward by gravity, gained enough speed to punch through the magnetic field at the bottom of the container and escape, annihilating itself and an unfortunate atom of regular matter in the process. “To do the experiment, you're actually just turning down the current that makes the magnetic field,” Hangst tells Inverse. “You have a cloud of [anti-hydrogen atoms] bouncing around, and you let them go.” When that happened, about 80 percent of the anti-hydrogen atoms fell toward Earth. The rest, about 20 percent, were still bouncing upward fast enough to keep going. That’s pretty much the result you’d expect from a tiny cluster of regular hydrogen atoms bouncing around in a magnetic field, too. That suggests that matter and antimatter both feel the pull of Earth’s gravity in the same way, which means matter and antimatter are attracted, not repelled, by each other’s gravity. In other words, the experiment confirmed that matter and antimatter are drawn together, just like all the other mass in the universe, regardless of their weird properties. “If you walk down the halls of the department and ask the physicists, they would all say that this result is not the least bit surprising, but most of them will also say that the experiment had to be done because you can never be sure,” says University of California at Berkeley physicist Jonathan Wurtele, a coauthor of the study, in a recent statement. “You don’t want to be the kind of stupid that you don’t do an experiment that explores possibly new physics because you thought you knew the answer, and then it ends up being something different.”