6.2. A worked example
The easiest way to see what is going on is to work through a specific
example, the
m22 /
2 potential which we already saw in
Section 5.5. We'll see that we don't even
have to solve the
evolution equations to get our predictions.
H
2×10-5
(provided AG <<
H), so we need
m
10-6mPl.
Because the required value of m is so small, that means it is easy to
get sufficient inflation to solve the cosmological problems, without
violating the classicality condition
V < mPl4. That implies only that
<
mPl2 /
m
106mPl, and as
Ntot
2
2 /
mPl2, we can get up to about
1013 e-foldings in
principle. This compares extremely favourably with the 70 or so actually
required.