Arvin Ash

CMB: What the Oldest Light Reveals about the Nature of the Universe | Cosmic Microwave Background (2021x19)

Udgivelsesdato: Jun 12, 2021

Get your SPECIAL OFFER for MagellanTV here: https://try.magellantv.com/arvinash - It's an exclusive offer for our viewers! Start your free trial today. MagellanTV is a new kind of streaming service run by filmmakers with 3,000+ documentaries! Check out our personal recommendation and MagellanTV’s exclusive playlists: https://www.magellantv.com/genres/science-and-tech Chapters: 0:00 - Speed of light and the past 1:24 - Cosmic Microwave Background 2:55 - What the early universe looked like 3:24 - What caused transparent universe 4:45 - Why is CMB not Gamma Rays? 5:51 - CMB - perfect Black Body 6:02 - What is a black body? 7:02 - Temperature of CMB 7:31 - Isotropy of the universe 8:15 - Why are there galaxies? 9:22 - Where did anisotropy come from? 10:14 - Evidence for cosmic inflation 11:14 - Why is the universe flat? 13:07 - Evidence for Big Bang 13:54 - Can we know anything prior to CMB? Join my Patreon: https://www.patreon.com/arvinash Outro artist of the week: Oleksandr Koltsov, "Classic House 90s Rave Music" Summary: If we look as far out as possible, we would see a uniform glow of low level radiation in all directions. This is called the cosmic microwave background, or CMB. It is the oldest light in the universe. And it can tell us a lot about its early history. Before the CMB, the universe was an opaque and featureless. About 380,000 years after the big bang, the universe cooled to around 3000 Kelvin, allowing electrons to combine with protons to form atoms. The universe then became transparent, because photons were free to travel from one end of the universe to the other, without being scattered by electrons. Why is this light from the very early universe microwave light, instead of higher energy gamma rays? 3000 K was not energetic enough to be gamma rays. In the 13.7 billion years it took for the light to reach earth, space expanded, causing the wavelength of photons to increases to microwaves. The CMB is the most p