D-Wave, the company that built the thing, calls it the world’s first quantum computer, a seminal creation that foretells the future of mathematical calculation. But many of the world’s experts see it quite differently, arguing the D-Wave machine is something other than the computing holy grail the scientific community has sought since the mid-1980s.

No doubt, the argument will continue. But today, researchers at the University of Southern California published a paper that comes that much closer to showing the D-Wave is indeed a quantum computer. USC houses and operates the D-Wave system owned by Lockheed, and the researchers — led by Daniel Lidar, a professor of electrical engineering, chemistry, and physics — say they have at least shown the machine is not using a computing model known as “simulated annealing,” which obeys the laws of classical physics (the physics of everyday life) rather than the more elusive properties of quantum physics.