Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thornhill, de Broglie and the kinetic theory of electromagnetic
  radiation   In 1983, Thornhill showed that Planck's energy distribution for a black-body
radiation field could be derived for a gas-like aether with Maxwellian
statistics. Further, it was shown that the frequency of electromagnetic waves
correlates with the energy per unit mass of the particles, not with their
energy, thus differing from Planck's quantum hypothesis. He pointed out that de
Broglie, in a paper of 1922, was on the way to achieving this result but did
not pursue the matter to its logical conclusion. Here a translation of de
Broglie's paper is presented to draw attention to this point. Some brief
additional comments are included also.

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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
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The categories of this paper are: eess
37
The categories of this paper are: supr-con
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The categories of this paper are: alg-geom
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The categories of this paper are: mtrl-th
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The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph
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The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph