There's also a theory that our universe is a 3-D hologram that was spawned from a black hole in a 4-D universe [1]. Would there be any way to test this theory as well?
That actually makes a lot of sense. For quite a while, I've been trying to imagine some rules for how some parent system might guide the laws of physics behind our universe, and your comment seems to have lit a bulb in my head. I haven't yet read the source link and I wish I could offer more input on it right now, but I'll have to check it out later.