The idea that an infinite number of parallel worlds could exist alongside our own is hard to wrap the mind around, but a version of this so-called Many Worlds theory could provide an answer to the controversial idea of quantum mechanics and its many different interpretations.
Bill Poirier, a professor of physics at Texas Tech University in Lubbock, proposed a theory that not only assumes parallel worlds exist, but also says their interaction can explain all the quantum mechanics "weirdness" in the observable universe.
Poirier first published the idea four years ago, but other physicists have recently started building on the idea and have demonstrated that it is mathematically possible. The latest research was published Oct. 23 in the journal Physical Review X.
Quantum mechanics is the branch of physics that describes the rules that govern the universe on the microscopic scale. It tries to explain how subatomic particles can behave as both particles and as waves. It also offers an explanation about why particles appear to exist in multiple positions at the same time. [The 9 Biggest Unsolved Mysteries in Physics]
This fuzzy clump of possible positions is described by a "wave function" — an equation that predicts the many possible spots a given particle can occupy. But the wave function collapses the second anyone measures the actual position of the particle. This is where the multiverse theory comes in.
Some physicists believe that once a particle's position is measured, the many other positions it could take according to its wave function split off and create separate, parallel worlds, each only slightly different from the original.
Hugh Everett was the first physicist to propose the possibility of a multiverse — an infinite number of parallel universes that exist alongside our own. He published his "Many Worlds" theory in the 1950s, but the idea was not well-received in the academic world.
Everett ended his career in physics shortly after getting his Ph.D., but many physicists now take the multiverse and parallel-worlds idea seriously. Poirier reworked the Many Worlds theory into the less abstract "Many Interacting Worlds" (MIW) theory, which could help explain the weird world of quantum mechanics.
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