Where Does Light Get Its Speed From?

Every photon in the universe - from a candle flame to a gamma-ray burst thirteen billion light-years away - travels at exactly the same speed through empty space. Not approximately. Exactly. Nothing pushes it. Nothing accelerates it. It is never slow, never fast, only this one speed. But why? In this deep dive, we uncover one of the most profound questions in all of physics: where does the speed of light actually come from? You will discover why the source of a photon controls its energy, frequency, direction, and polarization - but not its speed. Why photons never begin at rest and accelerate up to lightspeed. Why higher-energy photons do not travel faster than lower-energy ones. Why light appears to slow down in glass, water, and diamond - and why that is not what it seems. And most importantly, why the vacuum speed of light is not really a property of light at all, but a fundamental feature of the geometry of spacetime itself. We’re now live on Spotify 🎧 https://open.spotify.com/show/033itE9... Sources: Einstein, A. (1905). "On the Electrodynamics of Moving Bodies." Annalen der Physik. Maxwell, J. C. (1865). "A Dynamical Theory of the Electromagnetic Field." Philosophical Transactions of the Royal Society of London. Michelson, A. A. & Morley, E. W. (1887). "On the Relative Motion of the Earth and the Luminiferous Ether." American Journal of Science. Feynman, R. P., Leighton, R. B., & Sands, M. The Feynman Lectures on Physics, Volume I. California Institute of Technology. Griffiths, D. J. Introduction to Electrodynamics. Cambridge University Press. Hashtags: #SpeedOfLight #Physics #SpecialRelativity #Einstein #Spacetime #QuantumPhysics #Cosmology