Question

Why there should be minimum e foldings for inflation?

Answer 1

From what I understand, this fits extremely well with the basic chaotic inflation model given by V(Φ)=λΦ4V(Φ)=λΦ4.

We also know that amplitude of density fluctuations is ≈10−5≈10−5 and Energy scale of inflation is around 10161016 GeV.

My question: Given also this information, can we now make an educated guess for how many e-foldings happened during inflation ? Or at least a theoretical lower (upper ?) bound ?

PS: I am only referring to inflation of the patch of space that now contains our observable universe, not inflation of Universe as a whole.