The End of Matter? - Katherine Blundell

0:00 // Introduction — black holes are real and out there 0:57 // History — John Mitchell's dark star in 1783 4:32 // Escape velocity — how fast do you need to go to escape gravity? 9:31 // The event horizon — the point of no return 11:48 // What happens to matter near a black hole? 14:05 // Angular momentum — why black holes produce fireworks not just silence 21:33 // Accretion discs — matter spiralling in like planes over Heathrow 24:05 // Radio galaxies — jets half a million light years long 29:00 // The Event Horizon Telescope image of 2019 31:13 // Microquasars — speeded-up scaled models in our own galaxy 38:00 // Global Jet Watch — a network of telescopes to track black hole jets 44:03 // Spin-offs — teaching girls in India and South Africa through telescope access 50:54 // Why studying black holes matters — and how it gave us Wi-Fi Black holes give rise to some of the most spectacular phenomena we see in the cosmos. They significantly distort space-time and they grow by stealing material from other stars. This talk will separate science fiction from science fact and elucidate what we know about these mysterious objects, and how they have shaped, and continue to shape, our Universe. This lecture was recorded by Katherine Blundell on the 20th of November 2019 Katherine was appointed Gresham Professor of Astronomy in 2019. She is a Professor of Astrophysics at Oxford University and a Research Fellow at St John's College. Before this she was one of the Royal Society's University Research Fellows, a Research Fellow of the 1851 Royal Commission, and a Junior Research Fellow at Balliol College, Oxford. Her research interests include the evolution of active galaxies and their life cycles, the accretion of material near black holes and the launch and propagation of relativistic jets (jets of plasma emitted by some black holes). In her research she uses electromagnetic imaging and spectroscopy, as well as computational techniques. She is also a renowned science communicator and set up a worldwide network of five schools-based Global Jet Watch observatories, which collect data on evolving black hole systems and nova explosions in our Galaxy, helping to inspire the next generation of scientists in South Africa, Chile, Australia and India. Her awards include a Philip Leverhulme Prize in Astrophysics, the Royal Society's Rosalind Franklin Medal in 2010, the Institute of Physics Bragg Medal in 2012, the Royal Astronomical Society's Darwin Lectureship in 2015 and an OBE for services to astronomy and the education of young people in 2017. The transcript of the lecture is available from the Gresham College website: https://www.gresham.ac.uk/watch-now/e... Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham College's mission, please consider making a donation: https://www.gresham.ac.uk/get-involve... Website: https://gresham.ac.uk X: https://x.com/GreshamCollege Facebook: Facebook: greshamcollege Instagram: Instagram: greshamcollege Bluesky: https://bsky.app/profile/greshamcolle... TikTok: TikTok: greshamcollege Support Us: https://www.gresham.ac.uk/get-involve...