Fresh from the clogged tubes of teh intarwubs…
"Most of inflation's testable theoretical predictions have been confirmed. "Inflation is a key and somewhat indispensable part of our current understanding of how our universe began and evolved," Aguirre says. But the theory of cosmic inflation, proposed by MIT cosmologist Alan Guth in 1981, implies that it didn't just happen once, in our part of the cosmos, but rather keeps happening, inflating other patches of space like bubbles forming in a glass of beer.
This 'eternal inflation' creates other 'bubble universes' that likely have different properties from our own universe. In some bubbles, the electromagnetic force might be so weak that it can't hold atoms together, or the expansion rate might be so fast that galaxies can't form. "