Is the universe just part of a cluster that revolves around something bigger still?

Answer 1

According to current theory, no

But this superstring theory or M-theory do predicts multiverse system, or parallel uninverse. Out universe is just on one membrane and there are parallel membrane which holds other universe.

From my understanding, all fundamental building blocks of matter and energy, fermion and boson are attach to this membrane this is why we do not interact with other parallel universe thus we'll never be able to find or feel them. However the theory also predicts that only gravity is not attach to the membrane and so it may escape to other parallel universe. So theoritically and purely theoritically, we may one day, somehow, detect their presence through the graviton emitted by other parellel universe.

Anyway that's still a far far away idea as m theory still a theoritical physics and had not been proven yet.

I got those info from this educational movie The Elegant Universe.

Answer 2

This is only possible in Hollywood. We know that our universe is expanding, so if our universe was rotating around something bigger, the edge of our universe closest to the 'bigger something' would get sucked in by gravity and the expansion. This would knock the whole universe out of balance. It may have been possible before the Big Bang though???

Answer 3

No, the universe, by definition contains all matter.