Mathematically, why is the Rayleigh-Jeans fit to blackbody radiation obviously incorrect in retrospect? Rayleigh treated the speed of light, c, as a variable rather than as the constant derived by Einstein. The constant terms in the Planck equation use the wrong value of c, the speed of light constant. As wavelength decreases, lambda^5 continuously decreases. As the frequency increases, the term on the bottom of the Planck equation goes to zero.
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The Rayleigh-Jeans fit to blackbody radiation is based on classical physics and assumes that the energy of the radiation is directly proportional to the frequency. This leads to the Rayleigh-Jeans law, which predicts that the intensity of radiation increases Show more…
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