Everett’s many worlds interpretation of quantum mechanics says that there is a single wave function for the entire universe, and at the moment of measurement, the universal wave function splits in two. You see one measurement, and the you in the other universe sees another measurement. Universe Splitter lets you play with this theory. Type two choices into the app. The app will split the wave function in two by activating a quantum device that will send a single photon into an “either/or” state. Then, the app will tell you which universe you’re in. Unfortunately, Many Worlds says that the universes can’t communicate with each other, so you’ll never be able to talk to your copies. App Store: Universe Splitter – US$1.99
Check It Out: Universe Splitter Lets You Play With Quantum Mechanics