What happens to TIME in a black hole? (And why physicists can’t agree)

AD | Download UPDF with an exclusive special offer: https://updf.com/updf-sales-promotion/?utm_source=Youtube-drbecky-2610-liki&utm_medium=en&utm_campaign=liki202610&packageKey=overseapromotion Free UPDF download: https://updf.com/download/?utm_source=Youtube-drbecky-2610-liki&utm_medium=en&utm_campaign=liki202610&packageKey=overseapromotion OCR with UPDF: https://updf.com/ocr-pdfs/?utm_source=Youtube-drbecky-2610-liki&utm_medium=en&utm_campaign=liki202610&packageKey=overseapromotion In a black hole, time might end, or loop, or become a place in space, or become wildly unpredictable. And us physicists cannot agree which one actually happens. I think most people when they’re taught about black holes are taught a simplified version, that you fall in, and you end up in the middle crushed into an infinitely small point, a singularity. Which as you’re falling towards does weird things to time. But that describes a version of black holes that don’t exist in the real Universe (the Schwarzschild solution). Real black holes spin, and spin changes everything. Including the nature of the singularity itself, which becomes a donut shape (the Kerr solution). At least, an infinitely thin donut. Which does even weirder things to time, perhaps even making time travel possible. I’m going to walk you through first what is a black hole, what happens to time in a non-rotating black hole? What actually happens to time in a more realistic rotating black hole? And why physicists cannot agree on what’s going on, and hope that if we only had a theory of quantum gravity we might be able to solve this... Papers mentioned: Hamilton & Avelino (2010) - https://arxiv.org/pdf/0811.1926 Porras-Valverde & Forbes (2026) - https://arxiv.org/pdf/2610.27061 Wagner (2021) - https://itp.uni-frankfurt.de/~hees/gen-phys/derivation-of-the-kerr-metric-Wagner.pdf Einstein (1915) - https://etienneklein.fr/wp-content/uploads/2016/01/Relativit%C3%A9-g%C3%A9n%C3%A9rale.pdf Penrose (2002) - https://the-center-of-gravity.com/documents/145/Roger-Penrose_Gravitational-Collapse-The-Role-of-General-Relativity.pdf Shah (2025) - https://nhsjs.com/2025/investigating-ring-singularities-at-the-centre-of-kerr-black-holes/ Previous videos: https://www.youtube.com/watch?v=jRLNVvsxfFo 00:00 - Introduction 02:16 - I - What is a black hole? 06:07 - II - What happens to time inside a static black hole? 08:32 - III - What actually happens to time inside a realistic spinning black hole? 15:11 - IV - Why phy