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Guillem-Llobat X.,Max Planck Institute For Wissenschaftsgeschichte | Guillem-Llobat X.,University of Valencia
Annals of Science

In the late-nineteenth century food production and trade were greatly transformed. Changes in the food chain gave rise to new problems connected with food safety and food quality, which caused new controls to be introduced throughout Europe. In this paper I will contribute to ongoing debates by focusing on the regulation of saccharin in an agrarian city in the south of Europe, Valencia. The laboratory-made sweetener was introduced into the food market at the turn of the century, becoming highly controversial shortly afterwards. Several local groups of players got involved in this dispute. The sugar industry was not only an important stakeholder in the passing of some specific laws that were to constrain the use of saccharin, but also the main driver of regulation, primarily in periodswhen saccharin could become a serious competitor and reduce the sector's profit. Furthermore, the combined work of the sugar industry and themunicipal laboratories was essential for the implementation of regulations. It was in such municipal laboratories that scientists played a main role in regulation. My paper will address the commercial disputes linked to the use of saccharin and the limited role of science and scientists in its control. © 2011 Taylor & Francis. Source

Salisbury D.C.,Austin College | Salisbury D.C.,Max Planck Institute For Wissenschaftsgeschichte
Journal of Physics: Conference Series

In an article published in 1930 Léon Rosenfeld invented a general Hamiltonian formalism that purported to realize general coordinate, local Lorentz, and U(1) symmetries as canonical phase space transformations. He applied the formalism to a q-number version of tetrad gravity in interaction with both the electromagnetic field and a spinorial Dirac electron matter field. His procedure predated by almost two decades the algorithms of Dirac and Bergmann, and with regard to internal (non-spacetime) symmetries is fully equivalent to them. Dirac was in fact already in 1932 familiar with Rosenfelds work, although as far as I can tell he never acknowledged in print his perhaps unconscious debt to Rosenfeld. I will review the general formalism, comparing and contrasting with the work of Dirac, Bergmann and his associates. Although Rosenfeld formulated a correct prescription for constructing the vanishing Hamiltonian generator of time evolution, he evidently did not succeed in carrying out the construction. Nor did he have the correct phase space generators of diffeomorphism-induced symmetry variations. He did not take into account that some of the Lagrangian symmetries are not projectable under the Legendre transformation to phase space. © 2010 IOP Publishing Ltd. Source

Friedrich B.,Fritz Haber Institute | Hoffmann D.,Max Planck Institute For Wissenschaftsgeschichte | James J.,Fritz Haber Institute
Angewandte Chemie - International Edition

We outline the institutional history and highlight aspects of the scientific history of the Fritz Haber Institute (FHI) of the Max Planck Society, successor to the Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry, from its founding in 1911 until about the turn of the 21st century. Established as one of the first two Kaiser Wilhelm Institutes, the Institute began as a much-awaited remedy for what prominent German chemists warned was the waning of Germany's scientific and technological superiority relative to the United States and to other European nations. The history of the Institute has largely paralleled that of 20th century Germany. It spearheaded the research and development of chemical weapons during World War I, then experienced a "golden era" during the 1920s and early 1930s, in spite of financial hardships. Under the National Socialists it suffered a purge of its scientific staff and a diversion of its research into the service of the new regime, accompanied by a breakdown in its international relations. In the immediate aftermath of World War II it suffered crippling material losses, from which it recovered slowly in the postwar era. In 1952, the Institute took the name of its founding director and the following year joined the fledgling Max Planck Society, successor to the Kaiser Wilhelm Society. During the 1950s and 1960s, the Institute supported diverse research into the structure of matter and electron microscopy in its geographically isolated and politically precarious location in West Berlin. In subsequent decades, as Berlin benefited from the policies of détente and later glasnost and the Max Planck Society continued to reassess its preferred model of a research institute, the FHI reorganized around a board of coequal scientific directors and renewed its focus on the investigation of elementary processes on surfaces and interfaces, topics of research that had been central to the work of Fritz Haber and the first "golden era" of the Institute. Throughout its one-hundred-year history, the Institute's pace-setting research has been shaped by dozens of distinguished scientists, among them seven Nobel laureates. Here we highlight the contributions made at the Institute to the fields of gas-phase kinetics and dynamics, early quantum physics, colloid chemistry, electron microscopy, and surface chemistry, and we give an account of the key role the Institute played in implementing the Berlin Electron Synchrotron (BESSY I and II). Current research at the Institute in surface science and catalysis as well as molecular physics and spectroscopy is exemplified in this issue [Angew. Chem. 2011, 123, 10242; Angew. Chem. Int. Ed. 2011, 50, 10064]. A retrospect: The institute that was later renamed the Fritz Haber Institute began as a much-awaited remedy for the feared waning of Germany's scientific and technological superiority. The history of the Institutea-from its "golden era" in the 1920s and early 1930s, through war-related research during both World Wars, crippling losses following World War II, and impressive growth since the 1950sa-has largely paralleled that of 20th century Germany. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Creager A.N.H.,Princeton University | Creager A.N.H.,Max Planck Institute For Wissenschaftsgeschichte
Studies in History and Philosophy of Science Part C :Studies in History and Philosophy of Biological and Biomedical Sciences

This essay discusses three common issues arising from the special collection "100 Years of Cancer and Viruses." The first is the tension between small-scale and big-scale approaches to cancer research; the second is the difference between how physicians and biologists regarded cancer, and how they assessed the value of investigating viruses as a causative agent; and the third is how the pace and temporality ofscience have varied over the century of research on cancer viruses. An unpublished piece written by C.H. Andrewes in 1935, "A Christmas Fairy-Story for Oncologists," provides the touchstone for the commentary. © 2014 Elsevier Ltd. Source

Blum A.,Max Planck Institute For Wissenschaftsgeschichte
European Physical Journal H

The spin-statistics theorem, which relates the intrinsic angular momentum of a singleparticle to the type of quantum statistics obeyed by a system of many such particles, isone of the central theorems in quantum field theory and the physics of elementaryparticles. It was first formulated in 1939/40 by Wolfgang Pauli and his assistant MarkusFierz. This paper discusses the developments that led up to this first formulation,starting from early attempts in the late 1920s to explain why charged matter particlesobey Fermi-Dirac statistics, while photons obey Bose-Einstein statistics. It isdemonstrated how several important developments paved the way from such generalphilosophical musings to a general (and provable) theorem, most notably the use of quantumfield theory, the discovery of new elementary particles, and the generalization of thenotion of spin. It is also discussed how the attempts to prove a spin-statisticsconnection were driven by Pauli from formal to more physical arguments, culminating inPauli’s 1940 proof. This proof was a major success for the beleaguered theory of quantumfield theory and the methods Pauli employed proved essential for the renaissance ofquantum field theory and the development of renormalization techniques in the late1940s. © 2014, EDP Sciences and Springer-Verlag Berlin Heidelberg. Source

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