History
Contrary to popular opinion Planck did not quantize light. This is plain in his writing in his original 1901 paper and in the references in this paper to his earlier work. It is also plainly explained in his book "Theory of Heat Radiation" where he explains that his constant refers to Hertzian oscillators. The idea of
quantization was developed by others into what we now know as
quantum mechanics. The next step along this road was made by
Albert Einstein, who, by studying the
photoelectric effect proposed a model and equation whereby light was not only emitted but also absorbed in packets or
photons. Then, in 1924,
Satyendra Nath Bose developed the theory of the statistical mechanics of photons, which allowed a
theoretical derivation of Planck's law.
Nor did Planck derive his law in an attempt to resolve the "
Ultraviolet catastrophe", the name given to the paradoxical result that the total energy in the cavity tends to infinity when the
equipartition theorem of classical statistical mechanics is applied to black body radiation. Planck did not consider the equipartion theorem to be universally valid, so he never noticed any sort of "catastrophe" - it was only discovered some five years later by
Einstein,
Lord Rayleigh, and Sir
James Jeans.
From the Planck's law of black body radiation we can obtain the
Stefan-Boltzmann law by integrating the energy density over all wavelengths.
indefinite chopping up of physical quantities -
05-07-2005, 06:08 AM
Linear Mode
