^^^ Consider parallel universe theory. If the theory is accurate, where do the other universes exist? They exist in the same space that our universe exists in. But they exist in part of what we call 'empty space'. The reason why they aren't apparent to us is that they each have their own, separate, 'universal vibration' just as our universe has.
Take a look at any atom. The nucleus is a tiny section, with electrons revolving around it like planets around a star. What is in between the nucleus and the electrons? Empty space... except that it is fill with parts of other of the parallel universes.
In other words, all the empty space inside of the sphere of our solar system, is filled with other universes that are vibrating at a different universal vibration than our universe, and are connected with the whole of the cosmos as is our universe.
Are there an infinite number of universes? Nobody knows. Standard scientific theory doesn't even consider this in a big way. Few scientists are even thinking about it deeply.
Let's go on just a little, with something that needs to be realized to understand the immensity of what we are talking about here. With all of space being filled with universes, we are in general looking at an elastic solid - the aether - that fills the whole thing and makes up everything that exists. The only thing that separates all universes from each other is the different universal vibrations. So, this elastic solid is a conglomeration of vibrations. In some of his videos Nassim Haramein calls these vibrations the vibrations from the voice of God.
Where does material come from? It comes from contact points between two or more universes, where their vibrations touch on each other. A simple example might be when two stones are thrown into a pond simultaneously, but at different points. When the wave ripples cross each other, other ripples are made. When this happens in the parallel universes, that's where we get the subatomic particles, which are not particles at all, but are waves of vibration interference between universe vibrations from different universes.
Nassim Haramein doesn't often explain it this way, because people simply do not accept it (or maybe grasp it), and because he is spending his time trying to 'tame' universe vibration with machinery he is building and perfecting. In addition, the depth of understanding of the 'physics' that would go into explaining this is something the even AI couldn't grasp. It's tremendously complex, beyond understanding.
But the main point is that the thing that we consider to be 'nothing' doesn't exist. In a vacuum chamber, nearly all the pieces/particles of this universe have been removed. But the removal of them has allowed other of the parallel universes to fill in the so-called evacuated 'space'.