Kramers and the Forman Theses

Forman P. “Weimar culture, causality and quantum theory, 1918–1927: Adaptation by German physicists and mathematicians to a hostile intellectual environment”, Historical studies in the physical sciences, iii (1971), 1–115.

Bohr N. Kramers H. A. Slater J. C. , “The quantum theory of radiation”, reprinted in van der Waerden B. L. , Sources of quantum mechanics (Amsterdam, 1967), 159–76. This BKS paper is dated January 1924.

See Bohr Kramers Slater , op. cit. (ref. 2), 160; and van der Waerden , op. cit. (ref. 2), 13–14.

The complete correspondence between Kramers and Romein can be found in the Romein archive of the International Institute for Social History in Amsterdam. The passages quoted below are published here for the first time, and are translated by me.

Forman , op. cit. (ref. 1), 109–10.

Forman , op. cit. (ref. 1), 7.

Cf. Hendry J. , “Weimar culture and quantum causality”, History of science, xviii (1980), 155–80, pp. 169–71.

One important point seems to me that Forman's sociological explanation does not need to stop at the level of the (true or false) beliefs of individual scientists, but that it can also allow for the (mostly unintended) structural effects of these beliefs, which in this case were adaptations to the Weimar milieu (cf. Forman , op. cit. (ref. 1), 115). Another feature of the explanation is that what Forman refers to as the “Weimar intellectual milieu” is not just a set of “ideas”. These ideas were, or came to be, embedded in concrete social practices, as is apparent, for instance, from the reform of the secondary school curricula (cf. Forman , op. cit. (ref. 1), 23–25). That is to say, “ideology is material”.

For a recent and interesting approach to the problem of causal explanation in the social sciences, see Bhaskar R. , The possibility of naturalism. A philosophical critique of the contemporary human sciences (Brighton, 1979), ch. 2.

See Dorling J. , “A critique of Paul Forman's ‘Weimar culture, causality and quantum theory’”, unpublished paper presented at meeting of the British Society for the History of Science, July 1976 (typescript, 17 pp.), pp. 1–2.

Forman , op. cit. (ref. 1), 63.

Forman P. , “The reception of an acausal quantum mechanics in Germany and Britain”, in The reception of unconventional science , ed. by Mauskopf S.H. (Boulder, Colorado, 1979), 11–50, p. 14 (my italics). See also Forman , op. cit. (ref. 1), 107–8.

Forman , op. cit. (ref. 1), 115.

Forman , op. cit. (ref. 1), 98.

Bohr Kramers Slater , op. cit. (ref. 2), 165 (my italics).

E.g., held Bohr lebensphilosophische and anti-rationalistic views, too. Cf. Holton G. , “The roots of complementarity”, in Holton G. , Thematic origins of scientific thought (Cambridge, Mass., 1973), 115–61. Holton gives evidence of the influence of Kierkegaard, James and Hoffding on Bohr.

Cf. Forman , op. cit. (ref. 11).

He was acquainted with Spengler's ideas, as is apparent from a postcard to Romein dated 5 October 1921: “Did you succeed in reading Spengler's book about the Decline of the West. You surely won't have many good things to say about it”.

Letter from Kramers to Romein, 29 April 1923.

Letter from Kramers to Romein, 28 October 1924.

Kramers himself emphasizes this: “I very seriously mean everything that I have written” (in the same letter, 28 October 1924).

Kramers H. A. , “De wisselwerking tussen stof en straling”, Handelingen van het 20-ste Nederlandsch natuur- en geneeskundig congres (Haarlem, 1925), 164–7, p. 167. See also Kramers H. A. Holst Helge , Das Atom und die Bohrsche Theorie seines Baues (Berlin, 1925). The informative chapter on the interaction between matter and radiation (pp. 122–40) is written by Kramers alone, while the preface is dated March 1925. Here Kramers evaluates the BKS theory as follows: “at the time of writing these lines, there is not yet a definite answer on the side of the experimentalists. The new conception of the postulates … is yet in no way a finished theory; it is only an attempt to throw a little light in the great darkness of our ignorance about the course of the atomic processes, and it should, for the time being, be conceived as essentially a working-programme for the theorists” (p. 138). Although Kramers is cautious in this passage, there is no sign of any consideration of abandoning the theory.

Cf. Stuewer R. H. , The Compton effect (New York, 1975), 299–302. At that time even Bohr was anticipating an unfavourable outcome for the theory. Cf. Hendry , op. cit. (ref. 7), 178, note 93.

Kramers Hoist , op. cit. (ref. 21), 139.

Kramers , op. cit. (ref. 21), 167. Remember that it was one of the explicit aims of the BKS theory to provide an alternative to the light quantum hypothesis.

Kramers Holst , op. cit. (ref. 21), 139. It will be clear from the context of this paper, that I heartily disagree with this epistemological assessment by Kramers. Although the last sentence of the quotation might be true if “research method” is taken in a very (an all-too-) narrow sense, in general it seems incorrect. Epistemological preferences for certain types of theories or approaches can produce good, bad, or no effects, depending upon the specific circumstances, and may thus (consciously or not) influence the development of the science in question.

Brush S.G. , “The chimerical cat: Philosophy of quantum mechanics in historical perspective”, Social studies of science, x (1980), 393–447, pp. 397–8. Cf. also Brush S.G. , “Thermodynamics and history”, The graduate journal, vii (1967), 477–565, p. 530. In the case at hand the “confusion” can be found in the reviews of Hendry, op. cit. (ref. 7), 166, and more explicitly, Dorling, op. cit. (ref. 9), 3ff.

Cf. Forman, op. cit. (ref. 1), 41.

“Indeed it is difficult to understand how contemporary observers generally failed to recognize in Mach, Ostwald, and their cohorts a quasi-romantic movement parallel in several respects to Lebensphilosophie“, Forman , op. cit. (ref. 1), 19; see also pp. 45–46.

See the letter quoted in ref. 19, Section 4.

Quoted in van der Waerden, op. cit. (ref. 2), 20. Hendry's characterization of Kramers's dispersion formula as a “simple generalization” is rather simple compared with this judgement by Born (only mathematically, not physically, the generalization is simple), and for his assertion of an explicit dependence upon Born's work he gives no real evidence. See Hendry J. , “Bohr-Kramers-Slater: A virtual theory of virtual oscillators and its role in the history of quantum mechanics”, Centaurus, xxv (1981), 189–221, p. 204. See also Radder H. , “Between Bohr's atomic theory and Heisenberg's matrix mechanics: A study of the role of the Dutch physicist Kramers H.A.”, Janus, lxix (1982), 223–52.

With respect to this question of the assessment of Kramers's role, Slater's testimony about the timing and influence of the dispersion theory is also important: “On or about January 17, 1924, while the Bohr-Kramers-Slater paper was still being finished, Kramers showed me a theorem which he had proved shortly before, and which later proved to be practically as important in the development of matrix mechanics as the Compton effect was in the development of wave mechanics. This was the theorem which later became known as the Kramers-Heisenberg dispersion formula. Heisenberg did not enter the picture until later, in June 1924, when he came to Copenhagen to spend a year. I believe I was one of the few people who were told this theorem at such an early date, and it is not always realized what an important role Kramers played in these early discoveries. Fortunately I still have the piece of paper on which Kramers wrote down the formula in substantially the form which he later published in two letters to Nature in the late spring of 1924.” ( Slater J.C. , Solid-state and molecular theory: A scientific biography (New York, 1975), 15).

See Hendry , op. cit. (ref. 30). Cf. also Dorling , op. cit. (ref. 9) and Hendry, op. cit. (ref. 7).

Kramers H.A. Holst Helge , The atom and the Bohr theory of its structure (London, 1923), 133. In the German edition of this book (Kramers, Hoist, op. cit. (ref. 21), 123, the sentence “to get any further is impossible anyway” is added after this passage.

Kramers H.A. , “Vorm en Wezen”, Jaarboek der Rijksuniversiteit Utrecht (Utrecht, 1926), 57–80.

Note that this is essentially similar to his view of 1923. Cf. the preceding quotation.

Kramers , op. cit. (ref. 33), 63.

Kramers Holst , op. cit. (ref. 32), 43.

Kramers Holst , op. cit. (ref. 21), 137.

Kramers H.A. , “The quantum theory of dispersion”, reprinted in van der Waerden, op. cit. (ref. 2), 199–201, pp. 200–1. This paper is dated 22 July 1924.

Kramers H.A. , “On the behaviour of atoms in an electromagnetic wave field”, reprinted in Kramers H. A. , Collected scientific papers (Amsterdam, 1956), 321–31, p. 328. Note that in the years 1924 and 1925 there were as yet no experimental data available to test Kramers's dispersion formula in all its generality and secondly that the atomic model (the so-called virtual field model) on which the theory was based, was radically unclassical and certainly not obviously plausible.

Indeed, up to 1924, say, Kramers even was rather reluctant to abandon the notion of (unobservable) electronic orbits completely, as opposed to Pauli, Heisenberg and, to some extent, Bohr. Cf. Hendry , op. cit. (ref. 30), 195.

E.g., Jespersen Otto , Rector of the University of Copenhagen, notes at the dedication of Bohr's new institute for theoretical physics in 1921 that: “it is a delight that such an institution can be erected in this age which has such bad repute for materialism”, quoted in Bohr N. , Collected works, iii (Amsterdam, 1976), 24–25.

If not, then at most a causal psychological explanation might still be possible (given, of course, a suitable conception of psychological causation).

Forman's claim as to the (positive) evidential status of the reception of the BKS theory has been discussed and criticized by Dorling , op. cit. (ref. 9), 13–16, and by Hendry , op. cit. (ref. 7), 166.

E.g., both Forman and Hendry cite Pauli as a spokesman for their views; for the former he testifies to the “immediate and widespread assent which the [BKS] theory received in Germany”, and for the latter, he supports his assertion that “the [acausal] interpretation of the theory was almost unanimously rejected”. See Forman , op. cit. (ref. 1), 99; and Hendry , op. cit. (ref. 30), 190 and 202, and idem, op. cit. (ref. 7), 166.

See Serwer D. , “Unmechanischer Zwang: Pauli, Heisenberg, and the rejection of the mechanical atom, 1923–1925”, Historical studies in the physical sciences, x (1979), 189–256, and Hendry, op. cit. (ref. 30).

Cf. MacKenzie D. , “Notes on the science and social relations debate”. Class and capital, xiv (1981), 47–60, p. 54.