How the Universe Will End: What Changed in 2025

How the universe will end comes down to three possibilities: it can freeze, it can rip apart, or it can crunch. In 2025, two studies changed the odds. One said even dead stars evaporate far sooner than anyone thought. Another said the whole universe could stop expanding and collapse, with a total lifespan of about 33 billion years. In this case file we follow each ending all the way to the last black hole, check what those 2025 studies really calculated (and what the critics say), and look at the experiments that will tell us which ending is ours. Stay to the end for a first look at a case coming soon to the channel: could humans actually live on Mars? Chapters 0:00 Three ways the universe can end 0:59 Where we are now 3:13 The universe is running out of stars 4:19 The universe will hide its own history 6:47 The freeze: a tower of zeros 7:12 Red dwarfs, the last stars 9:28 White dwarfs freezing into crystals 10:56 Do protons last forever? 12:19 Black holes evaporate: a googol years 13:54 Heat death and entropy 15:54 2025: do dead stars evaporate sooner? 18:36 10^1100 vs 10^78 years 19:42 Is the physics right? 22:41 The Big Rip 24:10 Countdown: clusters to atoms 25:42 Does the data point to a rip? 27:09 The Big Crunch is back 28:08 The 2025 Cornell model: 33 billion years 29:49 What a crunch would look like 31:29 How seriously to take it 33:30 Wildcard: vacuum decay 34:42 How we'll find out 38:24 Verdict 40:35 Coming soon: could humans live on Mars? Main sources Falcke, Wondrak & van Suijlekom (2025), An upper limit to the lifetime of stellar remnants from gravitational pair production, JCAP: https://arxiv.org/abs/2410.14734 Wondrak, van Suijlekom & Falcke (2023), Gravitational Pair Production and Black Hole Evaporation, PRL 130, 221502: https://arxiv.org/abs/2305.18521 Ferreiro, Navarro-Salas & Pla, Comment on "Gravitational Pair Production and Black Hole Evaporation": https://arxiv.org/abs/2306.07628 (reply: https://arxiv.org/abs/2308.12326) Hertzberg & Loeb (2023), comment on gravitational pair production in de Sitter spacetime Luu, Qiu & Tye (2025), The Lifespan of our Universe, JCAP: https://arxiv.org/abs/2506.24011 DESI Collaboration (2025), DESI DR2 Results II: https://arxiv.org/abs/2503.14738 Caldwell, Kamionkowski & Weinberg (2003), Phantom Energy and Cosmic Doomsday, PRL 91, 071301 Adams & Laughlin (1997), A dying universe, Rev. Mod. Phys. 69, 337 Krauss & Scherrer (2007), The return of a static universe and the end of cosmology, Gen. Rel. Grav. 39, 1545 Page (1976), Particle emission rates from a black hole, Phys. Rev. D 13, 198 Super-Kamiokande (2020), proton decay search, Phys. Rev. D 102, 112011 Hyper-Kamiokande: https://www-sk.icrr.u-tokyo.ac.jp/en/... Sawala et al. (2025), No certainty of a Milky Way–Andromeda collision, Nature Astronomy Madau & Dickinson (2014), Cosmic Star-Formation History, ARA&A 52, 415 Andreassen, Frost & Schwartz (2018), lifetime of the Standard Model vacuum, PRD 97, 056006 Coming soon (Mars): Zeitlin et al. (2013), Science 340, 1080 (Curiosity RAD radiation dose) Images: NASA, ESA, CSA, STScI (Webb, Hubble), ESA/Webb, ESA/Hubble, EHT Collaboration, ESA (Euclid), NASA/JPL-Caltech/MSSS, NASA/JPL-Caltech/ASU, NASA/JPL-Caltech/University of Arizona (HiRISE), NASA/JPL-Caltech/SwRI. Full credits are shown on screen. All diagrams, animations and music were made for this channel. Freeze, rip or crunch: which ending would you bet on? And would you rather know? Tell me in the comments. #endoftheuniverse #cosmology #space