Andreas Trabesinger, a senior editor at Nature Physics, writes in News and Views this month (Nature Physics 4, 677; 2008):
“The past is by no means definite. It is rather open”, wrote the German historian of science Ernst Peter Fischer in Die Welt on 24 July 2006. In his column, Fischer introduced the “zeroth theorem of the history of science”; a discovery named after a person, the theorem says, did not originate from that person.
Take, for example, Avogadro’s number, named after Amedeo Avogadro, who asserted that there is the same number of molecules contained in a given volume of any gas at the same temperature and pressure. However, it was not the Italian savant who first estimated that number, but the Austrian scientist Johann Josef Loschmidt. Indeed, German-language texts sometimes refer to the number 6.022 1023 as ’Loschmidt’s number’. Much depends on who tells a story, and where and when. Fischer sees his zeroth theorem as an invitation to look with fresh eyes at the history of science, and in particular at how discoveries got their names.
That thought has now been picked up by J. David Jackson (Am. J. Phys. 76, 704–719; 2008). He has explored five examples from physics that illustrate Fischer’s zeroth theorem, and discusses the broader issue of credit-giving, and where it gives rise to inappropriate attributions. Jackson’s five examples take in various areas of physics, from the Dirac delta function to the Weizsäcker–Williams method of virtual quanta, to the Bargmann–Michel–Telegdi equation of spin dynamics. The journey includes encounters with big names such as Enrico Fermi or Nikola Tesla, but also with physicists whose biographies are far less commonly known, such as Oliver Heaviside, Llewellyn Thomas or Emil Wiechert. Their names are famous in some specific contexts, but little is known about their complete works."