Figure 15-14 The Observable Universe With and Without Inflation According to the inflationary model (shown in purple), the universe expanded by a factor of about 1050 shortly after the Big Bang. This growth in the size of the present-day observable universe—that portion of the universe that lies within our present cosmic light horizon—occurred during a very brief interval, as indicated by the vertical shaded area on the graph. The blue line shows the projected size of the present-day observable universe soon after the Big Bang if inflation had not taken place.