Something Is Passing Through You Right Now That Refuses to Stay One Thing

🔴 Support the channel and get exclusive content:   / meridianlabs   Right now, roughly one hundred trillion neutrinos are passing through your body every second, and most of them are no longer the same kind of particle that left the sun eight minutes ago. Nothing touched them. Nothing pushed them. Somewhere on the crossing they quietly stopped being what they were and became something else. The sun makes one kind of neutrino. You are being flooded by three. The most successful theory in the history of science, the Standard Model, says that should be impossible, because for a particle to change what it is in flight, it has to have mass, and the neutrino was the one particle everyone was certain weighed nothing at all. This is the story of how we found out that was wrong, and of the man who saw it decades before anyone else and was erased for it. His name was Bruno Pontecorvo. He was the youngest of Enrico Fermi's famous Via Panisperna boys in 1930s Rome, the physicist who invented the chlorine method later used to catch neutrinos from the sun, and in 1950 he vanished, defecting across the Iron Curtain into the Soviet Union in a disappearance that has never been fully explained. Cut off in the science city of Dubna, writing in Russian, wearing a reputation the West found inconvenient, he published in 1957 the idea that neutrinos oscillate, that they change flavor as they travel, and therefore that they must have mass. Almost nobody read it. When Ray Davis buried a tank of cleaning fluid a mile down in the Homestake gold mine and found two thirds of the sun's neutrinos missing, the field spent thirty years blaming the detector, blaming the model of the sun, blaming an honest chemist, anything rather than accept that the neutrinos were changing identity on the way, exactly as Pontecorvo and Gribov had written in 1969. The proof came too late for him. Super-Kamiokande confirmed atmospheric neutrino oscillation in 1998, the Sudbury Neutrino Observatory proved in 2001 and 2002 that the missing solar neutrinos had simply changed flavor and none were lost, and in 2015 the Nobel Prize in Physics went to Takaaki Kajita and Arthur McDonald for the discovery of neutrino oscillations, which shows that neutrinos have mass. Pontecorvo had been dead for 22 years. His name survives as the first letter of the PMNS matrix, spoken by every physicist who works on neutrinos, and his ashes were split between two graves in two countries, because even in death nobody could agree on what he was. This documentary follows the whole thread, from Pauli's ghost particle and Fermi's rejected paper to the open questions still unanswered tonight, the mass we cannot measure, the ordering we cannot determine, whether the neutrino is its own antiparticle, and whether this particle that refuses to hold an identity is the reason the universe contains anything at all. What is a neutrino, if it will not stay one thing. And if identity at the bottom of matter is not a property a thing has but an event that only happens when the universe is forced to answer, then what does that make you. Everything in this film is on the record. Primary sources and further reading below. Frank Close, Half-Life: The Divided Life of Bruno Pontecorvo, Physicist or Spy, Basic Books, 2015 Freeman Dyson, Scientist, Spy, Genius: Who Was Bruno Pontecorvo?, The New York Review of Books, 2015 W. Pauli, open letter to the Tübingen conference (Dear radioactive ladies and gentlemen), 1930 B. Pontecorvo, Mesonium and anti-mesonium, Soviet Physics JETP, 1957, and Inverse beta processes and non-conservation of lepton charge, 1958 V. Gribov and B. Pontecorvo, Neutrino astronomy and lepton charge, Physics Letters B 28, 1969 F. Reines and C. Cowan, Detection of the Free Neutrino: a Confirmation, Science 124, 1956 R. Davis, D. Harmer, K. Hoffman, Search for Neutrinos from the Sun, Physical Review Letters 20, 1968 Super-Kamiokande Collaboration (Y. Fukuda et al.), Evidence for Oscillation of Atmospheric Neutrinos, Physical Review Letters 81, 1998 SNO Collaboration (Q. R. Ahmad et al.), Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory, Physical Review Letters 89, 2002 The Nobel Prize in Physics 2015, Takaaki Kajita and Arthur B. McDonald, NobelPrize.org #Neutrino #NeutrinoOscillation #BrunoPontecorvo #Physics #ParticlePhysics #SuperKamiokande #SNO #StandardModel #SolarNeutrino #GhostParticle #NeutrinoMass #QuantumPhysics #NobelPrize #PMNS #EnricoFermi #WolfgangPauli #RayDavis #ColdWarPhysics #ScienceDocumentary #Documentary #NatureOfReality #FaultlinesStudio