In thinking about the universe story, we are having to get used to the very large numbers which relate to the age of the universe, now believed to be 13,700,000,000 years, and the size of the observable universe, about 10²⁵ metres. The inflationary theory relates to an event in the universe story at the equally problematical, from the point of view of our ability to conceptualise it, opposite end of the size and time spectrum, at the incredibly small, and lasting an incredible short period of time. The following diagram (redrawn from Alan Guth, The Inflationary Universe (Vintage, 1998), p.185) provides approximate estimates of the times and sizes involved. The precise figures are not known but in the interval of time between about 10^-38 and 10^-34 seconds the radius of the universe increased by about 50 orders of magnitude.

Both of axes of the graph are on logarithmic scales which means that time=0 and size=0, cannot be shown in the diagram and in the paper Alan Guth emphasises that neither the conventional Big Bang theory nor the Inflationary theory are theories about the ultimate beginning.