This paper investigates a well-known case of simultaneous discovery in twentieth-century chemistry, the origins of the concept of hybridisation, in the light of Kuhn's insights. There has been no ambiguity as to who discovered this concept, when it was "rst in print, and how important it was. The full-#edged form of the concept was published in 1931 independently by two American scientists John C. Slater (1900}1976) and Linus Pauling (1901}1994), although both of them had made their ideas public earlier: Slater (...) at the American Physical Society meetings in 1930, and Pauling in the Proceedings of the National Academy of Sciences in 1928. Slater and Pauling both argued for the necessity of using an s orbital as well as three p orbitals in the carbon atom in order to explain carbon's four valences and the tetrahedral structure of methane. The metaphor &hybridisation' for denoting this mix of s and p orbitals was "rst used by Robert S. Mulliken and J. H. Van Vleck before gaining currency with the scienti"c community around 1935.2 The concept of hybridisation was indeed indispensable for extending the quantum-mechanical interpretation of the chemical bond as an electron pairing from diatomic molecules to polyatomic ones. To be sure, the emergence of hybridisation attests to scientists' growing interest in exploring the borderland between physics and chemistry, a trend that led to the creation of physical chemistry in the late nineteenth century and of chemical physics and quantum chemistry in the 1920s and 30s. Slater and Pauling themselves experienced and on many occasions talked about the fruitfulness of interdisciplinary research; and historians have legitimately illuminated their works by examining them in this broad context.3 Yet the careful analysis of their research notes and published papers reveals that Slater and Pauling were working in quite disparate disciplinary traditions, with di!erent approaches, for di!erent audiences, and towards di!erent goals. The aim of this paper is to explore their di!erent routes to a common destination*hybridisation*and thereby to explicate tensions existing between physics and chemistry amidst the institutional and conceptual overlapping of the two disciplines. (shrink)

There is preserved in Suidas' Lexicon a story about Polycrates of Samos and the island of Delos. It is offered by the lexicographer as an explanation of the phrase τατ σοι κα πύθια κα δλια , when used in a colloquial sense to mean ‘it's all the same to you’. Polycrates had instituted a festival on Delos and asked the Pythia whether to call it by the one name or the other. The phrase, which was supposed to have been the (...) Pythia's reply, was taken to mean that it was all the same to Polycrates whatever he called it, and the death of Polycrates, coming soon after, was interpreted as the fulfilment of the prophecy. Suidas cites Epicurus and Menander for the phrase itself, which was therefore in familiar use by the end of the fourth century B.C. As for the story about Polycrates, it is quite likely that Suidas' ultimate source was some writer of about that period, such as Demon, περ παροιμιν. It is very much in the manner of his fragments. (shrink)

In Plutarch's two narratives of the recapture of the Cadmea by the Thebans, 379/8 B.C. , he speaks of three harmosts as in command of the Spartan garrison. This is the only instance in Spartan history where more than one harmost is mentioned as exercising authority in the same city, and it suggests the question: Was Thebes for some reason receiving different treatment from the other cities where we hear of harmosts in residence ?

Zosimus, after recording the foundation and immense growth of Constantinople, introduces a digression directed towards his purpose of justifying paganism against Christianity. ‘It has often indeed occurred to me to wonder how, when the city of the Byzantines has grown, so that no other can compare with it for prosperity and size, there was no prophecy delivered from the gods of our predecessors about its development to a better fortune. With this thought in mind I have turned over many volumes (...) of histories and collections of oracles, and with difficulty I happened upon one oracle said to be of the Sibyl of Erythrae or of Phaennis of Epirus. Nicomedes, the son of Prusias, put his confidence in this oracle, and interpreting it in an advantageous sense he took up war against his father, Prusias, at the persuasion of Attalus.’ Zosimus proceeds to quote twenty-one lines of hexameter verse, which have come down in a rather corrupt state, but of which the general sense is reasonably clear. They consist mainly of an obvious post eventum forecast of the Gallic invasion of Asia Minor in the third century B.C. (shrink)

Remembering Kolmogorov Content Type Journal Article Pages 1-3 DOI 10.1007/s11016-011-9540-6 Authors Paul M. B. Vitányi, CWI, Science Park 123, 1098 XG Amsterdam, The Netherlands Journal Metascience Online ISSN 1467-9981 Print ISSN 0815-0796.

H.B.G. Casimir's life, interests and works are intertwined with the important developments that have taken place in physics during this century. This book was compiled by his friends and admirers in honour of his 80th birthday and concentrates mainly on Casimir's achievements in the field of physics, though without ignoring the peripheral areas of the history and philosophy of physics in which he was greatly interested. The book is divided into four parts. Part I describes Casimir's teachers, Ehrenfest, Bohr and (...) Pauli, and will be of general interest due to the key role which these physicists played in modern developments. The articles do give new facts and provide new insights into the history of modern physics. Part II consists of essays on recent developments in various areas of physics in which Casimir has taken an active interest, such as the modern concept of time, statistical foundations of electrodynamic theory and field theory. The subjects covered in Part III have been selected because of Casimir's efforts in the industrial research area of physics. They cover past, present and future expectations in research. (shrink)