Small

[Gingerbaker]

As everything beyond our universe is infinitely large, does that mean also that things can be infinitely small. So you could have an infinite amount of small universes inside one of our known atoms…quarks…smaller and smaller…smaller…..?

[jim360]

Well, sure, multiverse theories are very much the realm of speculation, where pretty anything goes. There are a few concrete examples, but those aside, I'd agree that "We don't know" covers it pretty well. I might even add, to an extent, that we *can't* know. Probably.

But smaller universes inside our own? I confess for whatever reason I overlooked that part of the OP. I think I just assumed it meant to ask about substructures of substructures: materials made of molecules, molecules made of atoms, atoms of nuclei, nuclei of protons, protons of quarks, quarks of "quarklets", etc.

It's an idea that can be fun to think about, I suppose.