HEP Theory Journal Club

25 orders of magnitude “we” simply ignore in evolution of the baby universe!

Hossein Bazrafshan Moghaddam

McGill

“Quantum fluctuations during inflation got stretched, become classical and upon crossing the Hubble horizon freezes till re-entry horizon i.e. at CMB time when we observe them”. This is what cosmologists are used to believe it for years which means simply we assuming the fluctuations in early universe has no evolution for the period which spans 25 orders of magnitude in energy!! In this “short” talk I am going to attack this assumption through the window provided by a post-inflationary process namely reheating. I will show how enhancement in the evolution of fluctuations in matter sector happens when one considers gravitational fluctuations as well and how the story changes in overall. Then I will introduce δ N formalism and will show you how controversy in the issue arises in the community.