Can I get an anon to add a wrinkle to my brain?

Does out current understanding of physics allow us to reasonable conceptualize of a way to isolate a piece of universe from the rest of the universe?

Say, there's a 4D void (hypersphere?) around some region, and that creates an impasse for 3D folk like us. Does that make sense as a thing that could be possible with the physics we got?

I remembered some hack space opera I read once that had some alien race put some invincible forcefield around some hostile planets to keep them quarantined from the rest of the universe. The author obviously made up some nonsense fairy magic to justify it.

So I was just wondering how something like that could possibly work. Best I can come up is create a 4D bubble around a planet or whatever, and that's a barrier because we don't have a way to move through a fourth dimension.

I don't care if a machine to make it is possible, just curious if the end result works on paper or not.

Cheers