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Does the Planck Length Disrupt E=MC^2?

Sep 16, 2026 · 25m

Summary

This episode explores Doubly Special Relativity, a theory proposing that the Planck length remains invariant for all observers to resolve conflicts between quantum mechanics and general relativity. By modifying the standard dispersion relation, this framework suggests potential violations of energy conservation and energy-dependent light speeds. The discussion covers experimental constraints from gamma-ray bursts and the absence of vacuum Cherenkov radiation, which currently limit the strength of these proposed effects.

Topics discussed

Sponsor: LinkedIn ad campaign results Sponsor: Uber Eats game day delivery Intro: Extending Einstein's equation Galilean relativity and Newtonian mechanics Einstein's fix: Special relativity and Lorentz factor Conflict between General Relativity and Quantum Mechanics Sponsor: LinkedIn and Uber Eats Planck units and the scale of quantum spacetime The problem of invariant Planck length Doubly Special Relativity (DSR) proposal Sponsor: LinkedIn ad metrics Sponsor: Uber Eats game day delivery Modified dispersion relation (MDR) explained Breaking energy and momentum conservation Testing DSR: Photon pair production Astrophysical constraints on photon decay Vacuum Cherenkov radiation Energy-dependent speed of light Gamma ray burst observations and limits Conclusion: Current status of DSR Black Hole Friday merch sale promotion Sponsor: Citizens Bank and SVB Sponsor: McDonald's spicy McNuggets
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