16.5 For a potential of the form V(6) = V exp(), where is a positive constant, show that the inflation equations can be solved exactly to give R(t) = Ro (A)" 2/12 2 (t)=0+ In (1 Vo 2(6-12) 51%). Hence show that, provided < 2, the solution corresponds to a period of inflation. Show further that the slow-roll parameters for this model are = 1}{=, and so the inflationary epoch never ends. This model is known as power-law inflation