The rapid inflation didn’t last for long: some 10–36 seconds according to the current model. That’s a billionth of a billionth of a billionth of a billionth of a second. Yet in that time the inflaton is thought to have expanded space by a factor of 1078. It’s as if there was a build-up in pressure which suddenly got released, and once the release had happened, the universe settled down into the more sedate expansion we have picked up since.
