Some scientists theorize that the multiverse theory could potentially explain dark matter, suggesting that dark matter might be comprised of particles or matter from other parallel universes within the multiverse, which would only interact with our universe through gravity, making them difficult to detect directly; however, this is highly speculative and currently lacks concrete evidence to support it.
Discussion
A multiverse isn't impossible, but verifying it would be a job for psychics, not physicists.
There's a really good hint at what dark matter really is. The bigger the scale, the greater percentage of the matter is said to be "dark" - which means they don't know, actually, no serious physicist claims its real. If the proportion increases with the scale, the problem can't be what you're looking at. Its an error at the smallest level.