Negative neutrino mass. A 4.2σ tension with the standard model. Dark energy that may evolve over time. The DESI collaboration's latest data release isn't just adjusting parameters — it's threatening to break ΛCDM, the cosmological model that has anchored physics for 25 years. In this episode, I sit down with Kyle Dawson, lead spokesperson for the DESI collaboration, and Daniel Green, theoretical cosmologist at UC San Diego, to unpack the result that's quietly destabilizing modern cosmology: neutrinos appear to want negative mass to fit the data. That isn't a typo. We dig into why. We cover what DESI is actually measuring, why the cosmic microwave background alone can't resolve the tension, and what the Vera Rubin Observatory — coming online imminently — could either confirm or kill. If Rubin agrees with DESI, we are looking at the first crack in the standard cosmological model since dark energy itself was discovered in 1998. 🎯 Chapters: 📬 Join my mailing list to win a real asteroid fragment: https://briankeating.com/list ➡️ Subscribe and follow: 🔔 YouTube: https://www.youtube.com/DrBrianKeating?sub_confirmation=1 ✖️ Twitter/X: https://twitter.com/DrBrianKeating 📝 Newsletter: https://briankeating.com/list 🎧 Podcast: https://briankeating.com/podcast 📖 Blog: https://briankeating.com/cosmic-musings/ Into the Impossible with Brian Keating — conversations with the scientists rewriting the cosmic story. #NeutrinoMass #DESI #DarkEnergy #Cosmology #LambdaCDM #RubinObservatory #BrianKeating #IntoTheImpossible #ParticlePhysics #StandardModel