Discovery of Speed of Light Constancy · PhysicsBowl 2024 #14
Physics · modern-physics
Problem
The work of which of the following scientists is most closely associated with the discovery of the constancy of the speed of light? a. Albert Michelson and Edward Morley b. Christiaan Huygens and Augustin-Jean Fresnel c. Ernest Rutherford, Hans Geiger and Ernest Marsden d. Heinrich Hertz e. Willebrord SnellIntuitive explanation
The constancy of the speed of light—that light travels at the same speed in all inertial reference frames—is the foundation of special relativity. While Huygens and Fresnel developed wave theories of light, and Snell studied refraction, the Michelson-Morley experiment directly tested whether light's speed changes with Earth's motion through space. Their null result (finding no variation) provided the crucial experimental evidence that forced physicists to abandon the luminiferous ether and accept that is truly invariant.
Intuitive explanation
The constancy of the speed of light—that light travels at the same speed in all inertial reference frames—is the foundation of special relativity. While Huygens and Fresnel developed wave theories of light, and Snell studied refraction, the Michelson-Morley experiment directly tested whether light's speed changes with Earth's motion through space. Their null result (finding no variation) provided the crucial experimental evidence that forced physicists to abandon the luminiferous ether and accept that is truly invariant.