The many-worlds interpretation (MWI) is a theory in quantum mechanics that suggests the existence of multiple parallel universes or "worlds." However, the MWI itself does not inherently promote the idea of infinite spatial dimensions.
The concept of spatial dimensions is more closely related to theories such as string theory or certain branches of mathematical physics, such as Kaluza-Klein theory. These theories propose that the universe may have additional hidden spatial dimensions beyond the three (length, width, and height) that we commonly experience.
In the context of the MWI, the theory primarily deals with the behavior of quantum systems and the notion that all possible outcomes of quantum events occur in different branches of reality. It doesn't directly address the specific number of spatial dimensions or their properties.
It's important to note that theories like string theory, which involve higher-dimensional spaces, are still highly speculative and remain topics of ongoing research and debate within the scientific community. The MWI, although influential in the field of quantum mechanics, doesn't provide direct support or contradict such theories.