The Unknown Story Behind One of the Most Important Discoveries in Physics – with Jim Al-Khalili

One of the biggest discoveries in physics began with an experiment which almost everyone though wouldn’t reveal anything exciting. In the 1960s, physicists at Stanford's Linear Accelerator began firing high-energy electrons at protons – and uncovered evidence that these supposedly fundamental particles had a hidden structure. At the same time, two of the most influential theoretical physicists of the 20th century, Murray Gell-Mann and Richard Feynman, were developing ideas about the smaller constituents inside protons and neutrons. Gell-Mann called them quarks and Feynman called them partons. Were these just useful mathematical ideas, or were these particles really there? Through the remarkable story of the experiments that revealed quarks, Jim Al-Khalili explores how physicists uncovered the inner workings of matter, discovered the gluon and developed quantum chromodynamics (QCD), our modern theory of the strong force. Featuring first-hand recollections from scientists who were there, this film takes us inside the experiments, rivalries and unexpected breakthroughs that transformed particle physics. Chapters 00:00 The discovery of quarks 02:24 The Stanford experiment that changed physics 10:46 Bjorken, Feynman and Gell-Mann 18:50 Feynman visits the Stanford Linear Accelerator 22:13 What are quarks made of? 26:26 Asymptotic freedom: the mystery of the strong force 31:13 The hunt for gluons 37:12 Why most of your mass is energy Patreon Membership Becoming a Member on Patreon helps support the channel and fund our videos. Join us for early access to videos, bonus content and our infinite thanks:   / unbaffled   Infinite thanks to our Patreon Unbafflers John F Taylor Maria Sputnik Image credits • Paul Dirac and Richard Feynman at Jabłonna, 1962: Marek Holzman, CC BY 4.0 • Murray Gell-Mann portrait, Caltech, 1965: Caltech Archives/The Big T 1965 • 1966 high-energy physics conference participants: Donald Cooksey/Lawrence Berkeley National Laboratory • Richard Feynman, Caltech commencement, 1974: Caltech Archives/The Big T 1974 • Murray Gell-Mann and Mary Gaillard at CERN, 1972: CERN-PHOTO-7204175 • Clip from The Big Bounce (1960), Jerry Fairbanks Productions for Bell Laboratories/AT&T. Source: Prelinger Archives/Internet Archive • Portrait of James Bjorken (B. J.), SLAC theorist, 1968: SLAC National Accelerator Laboratory, Archives and History Office • CERN • Brookhaven National Laboratory • Fermilab • IACA • SLAC National Accelerator Laboratory DESY • Prelinger Archives Thanks to • Martin Breidenbach • Paul Söding • Aaron Groff, SLAC • Manuel G Gnida, SLAC • Hillary Smith, SLAC • Sven Ackermann, DESY • Joseph Piergrossi, DESY • Thomas Zoufal, DESY • Barbara Warmbein, DESY • Alexia Alexander Wight, UCL • Saskia Charity, University of Liverpool • Robert Thorne, UCL Books • The Second Creation: Makers of the Revolution in Twentieth-Century Physics – Robert P. Crease and Charles C. Mann • The Hunting of the Quark: A true story of modern Physics – Michael Riordan Papers • J. D. Bjorken, “Asymptotic Sum Rules at Infinite Momentum” (1969): https://doi.org/10.1103/PhysRev.179.1547 • E. D. Bloom et al., “High-Energy Inelastic \(e\)-\(p\) Scattering at 6° and 10°” (1969): https://doi.org/10.1103/PhysRevLett.2... • M. Breidenbach et al., “Observed Behavior of Highly Inelastic Electron-Proton Scattering" (1969): https://doi.org/10.1103/PhysRevLett.2... • D. J. Gross and F. Wilczek, “Ultraviolet Behavior of Non-Abelian Gauge Theories” (1973): https://doi.org/10.1103/PhysRevLett.3... • H. D. Politzer, “Reliable Perturbative Results for Strong Interactions?” (1973): https://doi.org/10.1103/PhysRevLett.3... • J. E. Augustin et al., “Discovery of a Narrow Resonance in \(e^+e^-\) Annihilation” (1974): https://doi.org/10.1103/PhysRevLett.3... • R. Brandelik et al. (TASSO Collaboration), “Evidence for Planar Events in \(e^+e^-\) Annihilation at High Energies” (1979): https://doi.org/10.1016/0370-2693(79)... • S. Dürr et al. (BMW Collaboration), “Ab Initio Determination of Light Hadron Masses” (2008): https://doi.org/10.1126/science.1163233 Follow us on social media   / unbaffledscience     / unbaffledscience     / unbaffledscience   https://bsky.app/profile/jimalkhalili... Get Jim’s latest book ‘On Time’ • https://press.princeton.edu/books/har... About Unbaffled Some ideas are hard to wrap your head around, but science doesn't have to be baffling. Unbaffled helps curious people, like you, develop an intuitive understanding of the science that shapes our world. Presented by Professor Jim Al-Khalili, we’re bringing you clear explanations of topics across science, technology and maths that will leave you informed and amazed. Monthly videos. Subscribe to be unbaffled. #QuantumPhysics #Quantum #JimAlKhalili #Unbaffled #science #historydocumentary #sciencedocumentary