PBS Space Time PBS Space Time

New Results in Quantum Tunneling vs. The Speed of Light

Oct 30, 2026 · 22m

Summary

This episode explores the theoretical and experimental aspects of quantum tunneling, specifically investigating whether particles can traverse barriers faster than light. The hosts discuss a new study using the Dirac equation that suggests tunneling can accelerate signal arrival, while a 2020 experiment utilized atomic spin as an internal clock to measure tunneling time.

Topics discussed

Sponsors: Subaru, SAP Concur, and Brilliant Introduction: Quantum tunneling and superluminal motion Recap: The mechanics of quantum tunneling The mystery of tunneling time and the Hartman effect Sponsors: SAP Concur, Subaru, and Sephora Why tunneling time definitions are ambiguous New theory: Dirac equation and FTL signaling limits Sponsors: SAP Concur, Subaru, and Sephora Experimental verification using spin-based clocks Conclusion: Causality and the speed of light limit Patreon shout-out: The Henry Van Styn Quantum Tunnel Q&A: Magnetic monopoles and Higgs field configurations Sponsors: SAP Concur, Subaru, and Sephora Q&A: Monopoles in black holes and Harry Potter tunneling Sponsors: LinkedIn, McDonald's, and Kuvasier
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