Physicists have proven that parallel worlds cannot be very different from each other

IN new study published in the journal Physical Review Letters, physicists have shown that the existence of parallel worlds, suggested by some theories of quantum mechanics, cannot lead to too large differences between them.

In the field of theoretical physics, superstring theories suggest the existence of parallel worlds (side A and side B). Although these universes cannot be distinguished, they are interconnected. A team of researchers from the University of Tsukuba has shown, using mathematical data, that under certain circumstances, dramatic transformations (“explosions”) that do not occur on the A side also do not occur on the B side.

The idea that our world could be one of many possible worlds arose as early as the 1950s as part of the so-called many-worlds interpretation of quantum mechanics. It assumes that with each quantum measurement, the universe branches into several copies, in which all possible outcomes of the measurement are realized.

However, it has not yet been clear how different these parallel worlds can be from each other. For example, is it possible to imagine a world in which all the laws of physics are the same as in ours, but gravity on Earth is twice that? Or a world in which all atoms are replaced by anti-atoms?

To answer these questions, the scientists used the mathematical tools of perturbation theory and showed that any deviations from our world should be very small and decrease as the number of quantum measurements increases. Thus, they proved that parallel worlds cannot be very different from each other.

In theoretical physics, specifically in string theory, the existence of parallel universes is assumed (this follows from the principle of mirror symmetry). It is assumed that there are two worlds (let’s call them world A and world B), which differ from each other by six-dimensional spaces (A and C) hidden in each of these worlds. However, because these spaces are so similar and invisible, we cannot theoretically determine which of the worlds we live in. The six-dimensional space A has been subjected to significant exploration, and under certain conditions extreme changes (eg explosions) do not occur in it.

However, recent discoveries have shown that the spaces A and B are transformed in a certain way, and their seemingly different objects correspond to each other. However, the nature and extent of this transformation has not yet been studied in sufficient detail, and the study of the properties of the space B has not yet been completed. As part of this study, the scientists mathematically analyzed whether space B had the same properties as space A. They projected known phenomena from space A into space B, making sure that even under certain conditions there were no explosions.

This breakthrough provides mathematical confirmation of one of the previously intuitively assumed similarities between worlds A and B. Although the researchers used some assumptions to prove the theorem, in the future they plan to clarify whether its truth holds even without these assumptions.

“ε-Regularity Theorem for a Flow of Mean Curvature of a Linear Sheaf”, Xiaoli Han and Hikaru Yamamoto, April 27, 2023, Asian Journal of Mathematics.

DOI: 10.4310/AJM.2022.v26.n6.a1