Late time and early time approximation for EOS

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
0 replies · 2K views
djymndl07
Messages
24
Reaction score
1
TL;DR
What are the the conditions for early universe when scale factor a is small so that we can approximate a complicated potential?
In the article https://arxiv.org/abs/1112.1682 effective potential in equation 16 is approximated for early universe and obtained equation 21 and for later time in equation 26. Some constraints are given in equation 4 and 5. Can anyone explain how this approximations are made? I was trying to calculate but could not find the desired expression.