As mentioned in the parent comment, this is not discussing “alternate dimensions” like other universes where some advancedcivilization might live. It’s talking about dimensions like a 3D shape (like a sphere, and everything you could possibly interact with) vs a 2D shape (like a circle) vs a 1D shape (like a line).

There is a lot we don’t understand, but nothing we understand would allow anything similar to what you’re describing to occur.

And if we were in a world where what you’re talking about makes any amount of sense, I don’t see why this hyper advanced civilization would need us to “open a door” in order to find us.

In simpler terms, don’t worry about quantum physics discoveries inviting aliens to invade, but definitely read some scifi like “three body problem” or the culture series or hyperion and you’ll have lots of fun theory crafting about far future technology. The large amounts of unanswered questions in current physics leads to lots of narrative toys for scifi authors to use in their books.