23. Cosmic inflation, UPDATED MAR 15, 2025.

Expansion of the Universe (Cosmology) section 23. Cosmic inflation, UPDATED MAR 15, 2025. 51 minutes. Several sections were updated and mistakes corrected. The lecture script for main course (not supplemental) videos is available here: https://drive.google.com/file/d/1BheW... , updated March 15, 2025. Note that the transcript provided by YouTube is automatically generated and may not be correct but the lecture script is what I used to create the video. The Planck time 0:47 The horizon problem 1:54 The flatness problem 9:34 The magnetic monopole problem 15:17 The solution: cosmic inflation 18:36 How inflation solves the flatness problem 25:21 How inflation solves the horizon problem 28:09 Clarifying horizon distance with cosmic inflation 35:21 How inflation solves the magnetic monopole problem 37:39 Cosmic reheating 42:17 Inflation in Planck times 45:45 CMB fluctuations from the inflaton field 47:19