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In this episode, the universe as we know it starts to come into focus. Dr. Katie Mack teaches John Green about the cosmic dark ages, the possibility of a multiverse, and the connection between the hot, dense early universe and today.

0:00 - Introduction
2:09 - CMB & The Cosmic Web
9:39 - The Possibility of a Multiverse
14:20 - The Inflaton Field
20:20 - Viewing Early Galaxies
24:22- The Surface of Last Scattering
30:35 - The Dark Ages of the Cosmos
34:25 - Dark Matter & Cosmic Dawn
47:01 - Feeling Awe

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