A LOSS OF IDENTITY: THE BIRTH OF QUANTUM STATISTICS 433
existence of analytically distinct parts of isotherms. It was not clear how this could
come about. The debate was inconclusive, and Kramers, the chairman, put the
question to a vote. Uhlenbeck recalls that the ayes and nays were about evenly
divided. However, Kramers' suggestion to go to the thermodynamic limit was
eventually realized to be the correct answer. Shortly afterward, Uhlenbeck with-
drew his objections to Einstein's result, in a joint paper with his gifted student, the
late Boris Kahn (a Nazi victim) [K2].
(4) Until 1938, the BE condensation had 'the reputation of having only a purely
imaginary character' [LI]. Recall that the Hel-Hell phase transition was not
discovered until 1928, by Willem Hendrik Keesom [K3]. In 1938, Fritz Londo
proposed interpreting this helium transition as a BE condensation. Experimen-
tally, the transition point lies at 2.19 K. It is most encouraging that Eq. 23.20
gives T = 3.1 K [L2]. It is generally believed but not proved that the difference
between these two values is due to the neglecting of intermolecular forces in the
theoretical derivations.
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