PBS Space Time PBS Space Time

Why String Theory is Wrong

Sep 14, 2026 · 24m

Summary

This episode explores the history and current crisis of string theory, tracing its origins from Kaluza-Klein extra dimensions to the convergence of five superstring versions into M-theory. It explains how dualities revealed these theories as facets of a single framework, yet highlights the "string landscape" problem where vast geometric possibilities prevent testable predictions. The discussion addresses the lack of experimental evidence for supersymmetry and questions whether physicists are prioritizing mathematical beauty over empirical truth, while also briefly touching on mirror univers…

Topics discussed

Beauty vs. Truth in Physics: The Weyl-Einstein Debate String Theory's Promise and the Question of Its Validity Kaluza-Klein Theory: Extra Dimensions and Electromagnetism Compactification, Charge, and Flaws in Early Kaluza-Klein Supersymmetry and the Five Versions of Superstring Theory Dualities: How Different String Theories Converge T-Duality: Winding Number vs. Momentum in Compact Dimensions S-Duality and the Limits of Geometric Interpretation M-Theory: Unifying String Theories in 11 Dimensions The Second Superstring Revolution and Supergravity The String Landscape: Calabi-Yau Manifolds and Predictions The Missing Supersymmetry and the Current Impasse Legacy of Weyl and the Future of String Theory Mirror Universes and the CPT Theorem Chirality of DNA and Handedness in a Mirror Universe Sponsorships and Outro
Listen ad-free on Castria