In December 2024, the head of Google's quantum computing lab said the company's new chip was so fast it must have borrowed computing power from parallel universes. The chip, called Willow, finished a test in under five minutes that would take the world's fastest supercomputer 10 septillion years, a number with 25 zeros, far longer than the universe has existed.
So the multiverse is not fringe. It shows up in serious science journals and major labs. The tweet just wrapped a movie plot around it.
The "many worlds" idea goes back to a Princeton physics student, Hugh Everett, in 1957. Every time a particle could go two ways, the universe splits, and both versions happen. In a 2025 survey of more than 1,000 physicists marking a century of quantum mechanics, about 15 percent picked it as their favorite explanation of reality. The older Copenhagen view won with 36 percent. Still, 15 percent is a lot of physicists, not a few cranks.
Now for the theory the tweet is probably mangling. In 2014, three physicists at Griffith University in Australia published a paper in Physical Review X saying parallel worlds are real and physically push against each other. Worlds that are almost identical push apart, like people elbowing for space in a packed room. That shoving creates every strange quantum effect, from particles slipping through solid walls to acting like a wave and a particle at the same time. One world gives you ordinary, predictable physics. A huge number of worlds gives you the weird rules of quantum mechanics.
In all of these pictures, your other copies cannot touch your life. The moment a quantum system bumps into its surroundings, the branches split and stop talking to each other. For an object about as heavy as a paperclip, the split happens faster than light can cross the center of a single atom. Even in the Griffith theory, the worlds interact through a blind force, not through choices. No version of you is sitting in another universe steering your life.
Google's bold claim got pushback too. Astrophysicist Ethan Siegel said you can explain everything Willow did without a single parallel universe. Physicist Sabine Hossenfelder pointed out that the test it passed just spits out a list of random numbers with no real-world use.
The image on the tweet is from the movie that swept the 2023 Oscars, where a woman's parallel selves bleed into one messy life. The true physics is stranger and lonelier than the movie. Those copies, if they exist, can never reach you and never change a thing.
@JonSno100@NightSkyToday Let the infinite versions of myself wage war in the quantum realm. Tomorrow, the mundane crown of reality still belongs to me, and it demands a monthly subscription