So get this.

Our entire observable universe is a "true vacuum." That means that in between stars and galaxies, there is a minimum amount of energy, caused by a few stray particles. In this true vacuum, all of the particles that make up us can exist. Now imagine a false vacuum. In these places, there is a greater amount of energy and pressure in each piece of space. One of these vacuums is already proven to exist- the electroweak false vacuum. In these vacuums, there is so much energy stored in each unit of space that very few or no particles can exist. However, since each of these vacuums have such a huge amount of energy, the space they occupy is expanding at a rate exponentially faster than the speed of light (since it's just empty space it can expand that fast). Our own true vacuum universe is expanding too- just not nearly as fast.

Now if these false vacuums existed in our observable universe, we'd obviously be able to see them. But what if instead of our universe containing false vacuums, a much larger false vacuum universe contained true vacuum bubbles of universes like our own universe? Each true vacuum bubble would begin with a "big bang" as energy from the false vacuum would suddenly be released. As the false vacuum universe inflates at an enormous pace, each of these little bubble universes expands like our own universe. Therefore, we will never be able to contact these other universes, but if the scenario above is correct, they exist.

Let the daydreaming begin.

*With apologies to Alex Villenkin.


PS, EXEC BOARD APPLICANTS- THIS IS NOT QUANTUM MECHANICS AND QUOTING THIS OR USING THIS THEORY WILL GIVE YOU NO POINTS.