If so, in a multiple BigBang (Universe or domain) scenario, there is no reason why some Universes /Domains would not interact with "our" Universe. And if so, such Domain Interactions would manifest in one way or the other. Dark Matter could be one such manifestation.
Ever wondered why shouldn't there be more than one Big Bang ? If there could be one Big Bang resulting in one Universe, there is no reason why there shouldn't be many more such BigBangs and many more Universes.
Dark Matter is around 28% of the Universe and is still an unresolved puzzle. Even after spending billions of USD, dark matter particle is as elusive as ever. And why not- after all what particle could be collision less and wouldn't absorb, reflect or refract even light?
Always wondered if the Universe came out of the cosmic egg with a BigBang, from where did that cosmic egg come from and where it was kept just before the BigBang.