Einsteins Theory of Gas Degeneration

After the brilliant success of the Bose-Einstein statistics with the light quantum gas, it was a natural suggestion to try it in the kinetic theory of gases also, as a substitute for the Boltzmann statistics. The investigation, which was undertaken by Einstein (1925), is based on the hypothesis that the molecules of a gas are, like light quanta, indistinguishable from each other. 

The calculations run exactly as in the light, quantum case, except that here a second subsidiary condition appears, on account of the conservation of the number of particles  

The determination of the probability of a definite distribution 25 follows the same lines as before. The calculation of the most probable distribution leads now, owing to the presence of the second subsidiary condition, to the equation 

We tEus find the Bose-Einstein law of distribution for atoms dN=F e) fed  

The quantity a is of course determined from the subsidiary condition 

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