How we plan to solve the 'Crisis in Cosmology'

00:00 - Introduction
00:44 - What is cosmology?
01:14 - What does a model of the Universe need to explain?
02:09 - Our best current model λ-CDM
04:26 - Measuring the expansion rate of the Universe with λ-CDM
05:34 - Measuring the expansion rate of the Universe with galaxies
08:14 - THIS is the "crisis in cosmology"
09:05 - Is the data or the model the problem?
11:43 - How are we going to solve the crisis in cosmology?
14:05 - What does the future hold?
17:01 - Brilliant
18:04 - Bloopers

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👩🏽‍💻 I'm Dr Becky Smethurst, an astrophysicist at 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.

[fordsfords]

Having a front-row seat is SO much more fun and interesting when you have a great play-by-play announcer. THANKS Dr. Becky!!!

[briansquibb]

I'm a "space enthusiast" and I could listen to you all day. You make extremely complex ideas and science understandable and very interesting. You should have your own TV show! Thank you for all you do and all your hard work and your amazing knowledge.

[ReformedGoldBug]

I'm betting the figure in 5 years will be smack dab between the measured and theoretical model because the universe has a sense of humor.

[richardmercer]

Just from general principles, the solution to "either A or B is wrong" is very likely to be "both A *and* B are wrong!".

[eeraa]

Omg Tysm for this! You have no idea how much it helps me even though I am just 13 I get inspired by you. I want to become an astrophysicist! A phd in astrophysics from Cambridge. I love all your videos like much. Tysm Dr.Becky you’re my idol ❤️

[fizyknaut]

You inspire me so much! I'm always looking forward to Thursdays because of your videos. You were also one of the reasons I started persuing Physics further, and started making videos on it as well. I'm a big fan- thank you!

[count_of_darkness]

2021: We have two estimates for the hubble constant. They disagree. We are in crisis. We need a third one.
2026: OK, we have three estimates for the hubble constant. They are precise enough... but they disagree. We are in crisis.

[TheOwlman]

I can't wait for the error bar to go down on the gravity wave measurement so that it ends up in the middle, then we will find out what the next level of crisis is called.

[samuela-aegisdottir]

I like that astronomers are framing the fact that the data doesn't fit the model as a good thing. It's not: "I am always 100% right, how dare you doubt", it is: "I am so excited to be wrong, because it means a lot more new science".

[michaelsommers]

When I was in school, the value of _H_ was about 75 +- 25. I'd say things have gotten better.

[theklaus]

You are Doing great. I’m in love with the universe, when I was a child we lived in a dark place. No street lights and I have seen northern lights 4 times. So once I took my parents magnifying glass and from that time. But I heard young people experience 70% less of the Milky Way because of lights. What a shame. But I think we are so lucky you and your community do a lot to educated me and others and even I’m not taking any degree I can explain to others what or how it all comes to end up as like now. And this is because of all these science show . I ended up studying music but I love cosmology as music. So thank you and keep them coming

[WhatAboutTheBee]

Fingers crossed for a third unique value, situated precisely betwixt the other two.

[overkillphil]

You did a “well better job” of making science videos than many observational astronomers.

[rander]

At my age (72), waiting five or more years is very frustrating. It also makes me want to live as long as possible to see how things (lots of things) turn out. I'll get some popcorn and sit back down in my front row seat.

[AvilaDreamer]

Hey there, Dr Becky!! ✨😊 Just wanted to say thank you for your OUTSTANDING content! As a "Space Enthusiast who Loves hearing about this [incredible] Stuff", I truly appreciate the way you explain these super complex topics. It clears the air, and removes so much of the confusing jargon that tends to get in the way of delivering the specific scientific messages you're trying to discuss and share. You do this all seemingly effortlessly, with a positive spirit and enthusiastic quality that is super contagious. You rock, girl! Thank you so very very much! 😋 Have a brilliant day - can't wait to hear more about this down the road. Oh, and you have a great singing voice too (just thought I'd toss that truth in as well!). 🤣 Ciao, hun!

[pspicer]

As an observational scientist, I believe we got a glimpse of the 7 year old Dr. Becky at 6:52. Another excellent video. Be safe all.

[NorthernMike]

I get a majority of my present "space talk" from this channel. Well done madam, keep it up👍

[FOGSmokebeer]

I solved it aged 8 it went something like "stuff happens what the hey" life's been simple since that day😯

[JGRGilbert]

This is great. Your previous Crisis in Cosmology was my fave.

[simian_essence]

Bravo! A fantastically clear & understandable exposition and explanation of the Crisis in Cosmology. The best by far that I've come across. Many thanks!!!