What If The Speed of Light Were NOT CONSTANT?
Summary
This episode investigates whether the speed of light is truly constant or if it has varied over time, exploring variable speed of light theories as alternatives to cosmic inflation and dark energy. The host explains why such models face significant challenges, including conflicts with Lorentz invariance and CPT symmetry, while noting that current evidence supports the invariance of light speed. The segment concludes with responses to viewer comments on superfluids, moving the Sun, and detecting gravitational waves from black hole collisions.
Topics discussed
Sponsors: Progressive and Pfizer
Introduction: Is the speed of light constant?
Relativity, Lorentz invariance, and the invariance of c
Why a variable speed of light is conceptually problematic
Sponsors: Progressive Truck and Anthropic
Sponsor: Botox for chronic migraine
Dickey's 1957 theory: Gravity as variable light speed
The horizon problem and VSL as an alternative to inflation
Moffat's VSL theory and symmetry breaking
Energy-dependent light speed and sponsors
Testing VSL via the fine structure constant
VSL violations of Lorentz and CPT symmetry
Conclusion: The status of variable speed of light theories
Sponsors and introduction to comment responses
Comment: Stirring superfluids and vortex formation
Comment: Moving the Sun and planetary orbits
Comment: Gravitational waves from black hole collisions
Comment: Supernova shadows and ozone depletion
Outro and final sponsors
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