TL;DR

Veritasium’s latest dives into Paul Dirac’s revolutionary work showing that allowing negative energy in his equations predicted the existence of anti-electrons (positrons) and even hinted at a mirror “anti-world.” From scrapping the original Schrödinger equation to formulating the Dirac equation, Derek Muller walks you through how theory met experiment (shout-out to Feynman, Heisenberg, and a very strange period in physics) and why antiparticles might be thought of as traveling backward in time.

Along the way you’ll get bonus context from experts Graham Farmelo and Cumrun Vafa, archival gems from Florida State and Caltech, and a clear timeline—from the Klein-Gordon equation’s failings to the bittersweet aftermath of Dirac’s prediction finally confirmed by the positron. Perfect for anyone fascinated by the weirdest corners of quantum mechanics.

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