Many thanks Chalnoth and mathman. Really what puzzled me was a sentence in one of Marcus Chown's books where he says that if inflation did occur then 380000 years after the Big Bang the universe would have been far smaller than if we assume expansion alone (with no inflation). I'm still not...
Why does inflation mean that the universe was much smaller at 380000 years after the big bang than we would predict from the Big Bang model alone? What would we expect the two sizes to be?