John L. Heilbron

Creativity and Big Science

Creativity and big science may sit uneasily together. Creativity is considered good in any amount; I do not recall ever hearing anyone complain of having more of it than he or she wanted. Big science, however, has its detractors. Some fret that it consumes resources better devoted to little science; others, that it routinizes work, bureaucratizes laboratory life and, to say the worst, suppresses creativity.

Rutherford–Bohr atom

Bohr used to introduce his attempts to explain clearly the principles of the quantum theory of the atom with an historical sketch, beginning invariably with the nuclear model proposed by Rutherford. That was sound pedagogy but bad history. The Rutherford–Bohr atom stands in the middle of a line of work initiated by J.J. Thomson and concluded by the invention of quantum mechanics. Thompson’s program derived its inspiration from the peculiar emphasis on models characteristic of British physics of the 19th century. Rutherford’s atom was a late product of the goals and conceptions of Victorian science. Bohr’s modifications, although ultimately fatal to Thomson’s program, initially gave further impetus to it. In the early 1920s the most promising approach to an adequate theory of the atom appeared to be the literal and detailed elaboration of the classical mechanics of multiply periodic orbits. The approach succeeded, demonstrating in an unexpected way the force of an argument often advanced by Thomson: becaus...

Bohr's First Theories of the Atom

When confronted with a case in which an accepted theory appears to fail, the physicist, like anyone else, has a choice of strategies. The most obvious, which is also that recommended by armchair methodologists, is to invent an entirely new theory; an example might be Johannes Keplers system of planetary motions. The most likely strategy, because it involves the least reconstruction, is to seek the slightest departure from received ideas that will save the phenomena; an example is John Couch Adamss supposition of the existence of a distant planet to account for irregularities in the motions of Uranus. In both of the examples the strategies worked: Keplers system, transformed by Newton, became the basis of the world of classical physics; Adamss calculations, and those of his French contemporary Urbain J. J. Leverrier, led to the discovery of Neptune.

J. J. Thomson and the Bohr atom

In 1911 Niels Bohr went to Cambridge, hoping to talk physics with J. J. Thomson; the discoverer of the electron was friendly but uninterested. Two years later Bohr published his epochal three‐part paper on the constitution of atoms and molecules, which challenged the program and goal of the Cambridge school. Bohrs new views soon won out; Thomsons quaint atomic models were declared worthless—old lumber fit only, as Ernest Rutherford put it, “for a museum of scientific curiosities.” For his part Thomson rejected the advances made by Bohr as meretricious superficialities obtained without, or at the price of, an understanding of the mechanism of atoms.

Franklin's physics

Benjamin Franklin usually receives good marks for his physics from those who have taken the trouble to study it. To contemporaries he was the “Kepler of Electricity” (Volta being the Newton), the “Modern Prometheus,” the “Father of Electricity.” Among moderns, Robert Millikan credits him with the discovery of the electron and brackets him with Laplace as the two greatest scientists of the 18th century. Millikan, whose promotion of Franklin was perhaps intended to facilitate a reappraisal of the relative contributions of himself and J. J. Thomson to the investigation of electrons, went too far. But one does not have to consider Franklin a Kepler, Newton, Prometheus or Millikan to perceive that he was one of the most important natural philosophers of the Age of Reason.