Scientists have developed a test, to check if the universe is really some massive, computer-style simulation like “The Matrix.” To get a handle on the strategy, think 3D video games. Designers build into games the laws of physics. When, for instance, a character drops a grenade, there's simulated gravity so the grenade falls to the ground. In games and other simulations, the rules of the universe are simplified, as if sketched with a thick magic marker that can't render fine detail. If physicists were ever able to spot a similar chunkiness in properties of the universe, then it could be it's all a giant computer simulation.