The work of a scientist is often something that doesn’t lend itself to regular hours. Experiments often require attention at regular internals over a prolonged period of time, and many experimental subjects don’t care about whether or not a scientist has to get his or her beauty sleep. There is little worse than the dreaded ’12 hour timepoint’.

But some scientists – principally theoreticians – like to keep strange hours. Julian Schwinger, probably the model for Good Will Hunting, rarely arrived at university until after 5pm, and worked through the night, famously solving equations his colleagues had left up on their blackboards during the day.

Despite the success that many of these nocturnal habits had (Schwinger won the Nobel prize, after all), other scientists didn’t approve of this sort of behaviour. Ernest Rutherford, famous for the nuclear theory of the atom, refused to allow his research staff to work after 6pm at night. After quizzing an an enthusiastic student about his work ethic, and being told the student liked to work all day and all evening, he replied ‘But when do you think?’.

Rules were not so strict, however, at the Institute for Theoretical Physics in Copenhagen, now named after its founder, Niels Bohr,  who founded it in 1921. Through this great institute came many of the great minds of atomic physics in its golden inter-war years. The institute attracted a vast array of different personalities from around the world. Two such people, brought together here were George Placzek and Robert Otto Frisch.

Placzek was a Czech theoretical physicist, ‘a bohemian in every sense of the word … speak[ing] ten languages more-or-less fluently and with a fine range of naughty verse in all of them’ in the words of Frisch, his experimentalist and perhaps more mild-mannered chum and colleague.

In collaboration this duo tested emerging ideas from Enrico Fermi‘s in Italy of the ‘compound nucleus’, a theory that predicted that atomic nuclei could absorb neutrons at much lower energies that that was thought possible previously, and which would mark a paradigm shift in the understanding of atomic physics.

On the threshold of this major discovery, Bohr urged the young pair to publish. But it wasn’t so easy. Placzek – the theoretician – didn’t get up out of bed until the early evening and worked through the night. The experimentalist Frisch, on the other hand, kept more conventional hours. Their obscure working practices began to attract attention from another colleague, George von Hevesy, a sardonic Hungarian chemist, and pioneer of radioactive tracing in biology. Frisch picks up the story,

Hevesy suffered from insomnia and often came to the laboratory at night. One day he said with his deep Hungarian voice, ‘Frisch, I see you around the lab at all possible times, do you never sleep?’ So I explained the reasons for staying up with Placzek, normally until 3, trusting him to put the radium in its bottle and switch off the counters after I had gone to bed. Hevesy, with a faraway look in his long melancholy face began to tell a story. ‘In the village where I lived as a boy,’ he said ‘they once caught a young wild pig which had lost its mother. and the put the pig together with a young domestic pig so that they should grow up in company; but that did not work. The wild pig was used to a nocturnal life and used to rummage all night, keeping the tame pig awake; and the tame pig didn’t let the wild pig sleep in daytime. So after a few weeks both pigs died.’

 

You can read more about Frisch, Hevesy and Placzek in Otto Frisch’s memoirs, ‘What Little I Remember’, Cambridge University Press. The quotes are from this book..