Does the expansion rate of the Universe CHANGE over time?! | DESI 1 year results

AD - Head to https://squarespace.com/drbecky to save 10% off your first purchase of a website or domain using code DRBECKY. | The first year of data from the Dark Energy Spectroscopic Instrument (DESI) survey has been released this month along with a few dozen scientific research papers delving into the data. The result that caught my eye was their investigation of the change in the expansion rate of the Universe with time using a "standard ruler" technique using Baryonic Acoustic Oscillations. The first year of data seems to be showing some disagreement with our best model of the Universe? But will those results hold with the next 4 years of observations...? DESI 1st year public release: https://www.desi.lbl.gov/2024/04/04/d... Papers that I showed plots from in this video: DESI collaboration III (2024): https://arxiv.org/pdf/2404.03000 DESI collaboration IV (2024): https://arxiv.org/pdf/2404.03001 DESI collaboration VI (2024): https://arxiv.org/pdf/2404.03002 00:00 Introduction 02:20 Chapter outline 04:03 What are Baryonic Acoustic Oscillations (BAO)? 06:30 What is a "standard ruler"? And how they allow you to calculate the expansion rate of the Universe 08:04 What the DESI collaboration found 08:46 Do their results agree with our best model of the Universe? 11:26 Bloopers Video filmed on a Sony ⍺7 IV Video edited by Jonny Hyman --- 📚 My new book, "A Brief History of Black Holes", out NOW in hardback, paperback, e-book and audiobook (which I narrated myself!): http://lnk.to/DrBecky --- 👕 My new merch, including JWST designs, are available here (with worldwide shipping!): https://dr-becky.teemill.com/ --- 🎧 Royal Astronomical Society Podcast that I co-host: podfollow.com/supermassive --- 🔔 Don't forget to subscribe and click the little bell icon to be notified when I post a new video! --- 👩🏽‍💻 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