The sausage illustrations of the age of the universe all demand an inflationary period after the Big Beginning, and that to explain the smooth temperature range throughout the later universe; but you do not need an explosive growth to have that. Example: All humans have a common normal temperature of 37 degrees, but the population explosion has only happened late, in the last 100 years. the common origin was the key. and is perhaps to the universes' uniformity too. everything has moved through the same time radius since the beginning.