The Horizon Problem | The Universe's biggest UNSOLVED mystery

If you’re struggling, consider therapy with BetterHelp #ad. Click https://betterhelp.com/drbecky for a 10% discount on your first month of therapy with a credentialed professional specific to your needs. | Ever wondered how the Universe looks roughly the same in all directions? Because, technically, it shouldn't. It doesn't make sense. So does that mean we're missing something in our physics? Something like inflation? Or is the universe cyclical, going through Big Bangs and Big Crunches? Or does the speed of light vary with time?

00:00 - Introduction
03:51 - What actually is the cosmic microwave background?
05:15 - What is the cosmic horizon?
06:21 - What is the "horizon problem"?
08:27 - Inflation - a solution to the horizon problem?
10:12 - Cyclical Universe - a solution to the horizon problem?
11:12 - Varying the speed of light - a solution to the horizon problem?
12:03 - But what about the "crisis is comoslogy"? Is it something else?
12:34 - Bloopers

Video filmed on a Sony ⍺7 IV

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👩🏽‍💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.


http://drbecky.uk.com
https://rebeccasmethurst.co.uk