Why Light Can Carry Momentum Without Having Mass

How can light push things if it has no mass? Every physics class teaches that momentum equals mass times velocity - no mass, no momentum. But light breaks this rule. Photons have zero rest mass, yet they carry momentum, exert pressure, and physically push on everything they touch. Right now, sunlight is pressing against the Earth with a force of hundreds of millions of pounds. In this video, we trace the full story - from Kepler watching comet tails bend away from the Sun over four hundred years ago, to Maxwell's shocking prediction that electromagnetic waves exert pressure, to Einstein's special relativity revealing that energy and momentum are linked independently of mass. We explore how Arthur Compton proved individual photons collide like billiard balls, how lasers use photon momentum to cool atoms to near absolute zero, and how solar sails could one day carry spacecraft to other stars using nothing but light. We’re now live on Spotify 🎧 https://open.spotify.com/show/033itE9... Sources & Further Reading: Einstein, A. (1905). "On the Electrodynamics of Moving Bodies." Annalen der Physik, 17, 891–921. Compton, A.H. (1923). "A Quantum Theory of the Scattering of X-Rays by Light Elements." Physical Review, 21(5), 483–502. Maxwell, J.C. (1873). A Treatise on Electricity and Magnetism. Oxford: Clarendon Press. Ashkin, A. (1970). "Acceleration and Trapping of Particles by Radiation Pressure." Physical Review Letters, 24(4), 156–159. Lebedev, P. (1901). "Experimental Examination of Light Pressure." Annalen der Physik, 6, 433–458. #physics #light #momentum #photons #Einstein #relativity #space