In an interesting article at New Scientist, they briefly talk about 4 different ways we can observe the multiverse. That is, we can kind of see other universes. The four methods are:
- The wave function – via wave function collapse. See also: Schrödinger’s Cat.
- Wave/particle duality – evidently the interference patterns come from photons in our universe reacting with those in another universe.
- Quantum computing – quantum computers may work by doing parallel processing across universes.
- Quantum Russian roulette – don’t think you’re immortal after not being killed by a quantum gun.