You’re unique. Aren’t you? One of the more creative hypotheses surrounding quantum mechanics posits the exact opposite. Though we can readily see only one world, quantum mechanics says that when we’re not observing the particles that make up that world, those particles exist in multiple places at once. There are many theories that attempt to grasp what this means, but one of the most tantalizing is Hugh Everett’s multiverse concept.
According to Everett, each time any particle interacts with the rest of the world, it splits into other versions of itself—each one following a different path of potentiality. Every one of those “versions” exists simultaneously in its own parallel universe. In this John Pavlus edit of a postsilence video, the 134 overlaid playthroughs represent the manifold possibilities Mario encounters as he progresses through his world. When Mario jumps on a pipe, for instance, he can be attacked by a Piranha Plant immediately, mid-air, or not at all. So when Mario splits each of those “others” is following that possible path concurrently. Of course, for those of us living outside Super Mario World, there’s no way to observe these infinite parallel universes. As the video notes, there have been mathematical proofs; but they confirm only that the hypothesis is consistent with what we do observe. In other words, the theory very much remains a theory.