Multiverse

I rediscovered the great thinker and writer Bertrand Russell. It occurred to me that the universe actually have a limited number of particles i.e atoms, so in that sense our universe must be finite.

"The number of atoms in the entire observable universe is estimated to be within the range of 1078 to 1082".

Even though the universe is constantly expanding, its sum of particles is in fact limited.

But what is beyond those particles?

Let's presume that the particles were emitted from a Big Bang theory and imagine that we live in one of those big bangs on billions of particles, expanding ever further, until it implodes on itself. Perhaps when it implodes on it's own gravity it will explode again. In short terms cyclical.

But why would there only be only one of these sphere shaped 'jellyfish-moving' - 'big-bang', there could be an infinite number of those.