Where did the Universe come from? – with Geraint Lewis

Modern physics is split in two. To explain the large-scale Universe, we talk of the curved and expanding spacetime of Einstein’s General Theory of Relativity. For the small-scale, we talk about probabilities and uncertainties and the language of quantum mechanics. Whilst these two pillars of physics are both supremely accurate and immensely powerful theories, they are, at heart, incompatible. But to understand the past, present and future history of the universe, we must get these two theories to play nicely together. Watch the Q&A here: Q&A: Where did the Universe come from? – w... Subscribe for regular science videos: http://bit.ly/RiSubscRibe This lecture was recorded at the Royal Institution on 2 December 2021. 0:00 Introduction 2:04 Historical guide to understanding the Universe 8:12 The difference between relativity and quantum mechanics 13:04 Uniting the two theories 16:39 Categorising research areas using the two theories 20:25 Understanding the Universe 27:58 Big bang nuclear synthesis 33:27 How do we understand what comes out of the big bang? 37:01 The balancing act of stars 39:35 What's happening in the heart of the Sun? 45:08 Getting elements out of stars and into the Universe 52:34 The future of the universe 55:13 Why don't dead stars collapse? 1:01:46 The struggle in describing Hawking radiation 1:04:28 Closing the chasm of ignorance Thumbnail image credit: Illustris Collaboration | https://www.illustris-project.org/media/ Geraint Lewis was born in South Wales and is a Professor of Astrophysics at the Sydney Institute for Astronomy, part of the University of Sydney's School of Physics. His research focuses on the 'dark side of the universe', the matter and energy that shapes our cosmos. Geraint is also a teacher, an author, and science communicator.​ As well as two books on cosmology, Geraint has published more than 400 hundred papers in international refereed journals. ---- A very special thank you to our Patreon supporters who help make these videos happen, especially: Andy Carpenter, William Hudson, Richard Hawkins, Thomas Gønge, Don McLaughlin, Jonathan Sturm, Microslav Jarábek, Michael Rops, Supalak Foong, efkinel lo, Martin Paull, Ben Wynne-Simmons, Ivo Danihelka, Paulina Barren, Kevin Winoto, Jonathan Killin, Taylor Hornby, Rasiel Suarez, Stephan Giersche, William Billy Robillard, Scott Edwardsen, Jeffrey Schweitzer, Frances Dunne, jonas.app, Tim Karr, Adam Leos, Alan Latteri, Matt Townsend, John C. Vesey, Andrew McGhee, Robert Reinecke, Paul Brown, Lasse T Stendan, David Schick, Joe Godenzi, Dave Ostler, Osian Gwyn Williams, David Lindo, Roger Baker, Greg Nagel, Rebecca Pan. --- The Ri is on Patreon: Patreon: TheRoyalInstitution and Twitter: Twitter: ri_science and Facebook: Facebook: royalinstitution and TikTok: TikTok: ri_science Listen to the Ri podcast: https://anchor.fm/ri-science-podcast Our editorial policy: https://www.rigb.org/editing-ri-talks... Subscribe for the latest science videos: http://bit.ly/RiNewsletter Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link. #OriginOfTheUniverse, #CosmologyExplained, #GeraintLewis, #BigBangTheory, #AstrophysicsInsights