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1.
As President of the Kaiser Wilhelm Society and its successor, the Max Planck Society, from 1946 until 1960, Otto Hahn (1879–1968) sought to portray science under the Third Reich as a purely intellectual endeavor untainted by National Socialism. I outline Hahn’s activities from 1933 into the postwar years, focusing on the contrast between his personal stance during the National Socialist period, when he distinguished himself as an upright non-Nazi, and his postwar attitude, which was characterized by suppression and denial of Germany’s recent past. Particular examples include Hahn’s efforts to help Jewish friends; his testimony for colleagues involved in denazification and on trial in Nuremberg; his postwar relationships with émigré colleagues, including Lise Meitner; and his misrepresentation of his wartime work in the Kaiser Wilhelm Institute for Chemistry.  相似文献   

2.
As the co-discoverer of nuclear fission and director of the Kaiser Wilhelm Institute for Chemistry, Otto Hahn (1879–1968) took part in Germany‘s nuclear-fission project throughout the Second World War. I outline Hahn’s efforts to mobilize his institute for military-related research; his inclusion in high-level scientific structures of the military and the state; and his institute’s research programs in neutron physics, isotope separation, transuranium elements, and fission products, all of potential military importance for a bomb or a reactor and almost all of it secret. These activities are contrasted with Hahn’s deliberate misrepresentations after the war, when he claimed that his wartime work had been nothing but “purely scientific” fundamental research that was openly published and of no military relevance.  相似文献   

3.
Max Planck Examines and Improves 50 years ago, the leaving president of the “Kaiser Wilhelm Gesellschaft”, Max Planck, visited the “Kaiser Wilhelm” institute of physical chemistry in Dahlem. Prof. Thiessen was its director.  相似文献   

4.
One of the less known aspects of the work of Ludwig Boltzmann (1844–1906) is that he was an advocate of aviation, one of the most challenging technological problems at the end of the 19th century. Boltzmann followed the work of the flight pioneers Otto Lilienthal (1848–1896), Wilhelm Kress (1836–1913), and Hiram S. Maxim (1840–1916) closely, and in a lecture in Vienna in 1894 and in a article in a Viennese newspaper in 1896 he advocated the provision of financial support for research in this field. I discuss Boltzmann’s involvement in aviation, and his related correspondence with Lilienthal and Kress.  相似文献   

5.
A guided tour of significant sides pertaining to the history of physics is conducted around the area of the Technische Universit?t and the Physikalisch-Technische Reichsanstalt in Berlin-Charlottenburg, of the Institutes of the former Kaiser Wilhelm Society in Berlin-Dahlem, as well as to some points of interest in the area of Potsdam.  相似文献   

6.
One of the longstanding attractions of the Deutsches Museum in Munich, Germany, has been its display of the apparatus associated with the discovery of nuclear fission. Although the discovery involved three scientists, Otto Hahn, Lise Meitner, and Fritz Strassmann, the fission display was designated for over 30 years as the Arbeitstisch von Otto Hahn (Otto Hahn’s Worktable), with Strassmann mentioned peripherally and Meitner not at all, and it was not until the early 1990s that the display was revised to include all three codiscoverers more equitably. I examine the creation of the fission display in the context of the postwar German culture of silencing the National Socialist past, and trace the eventual transformation of the display into a contemporary exhibit that more accurately represents the scientific history of the fission discovery.  相似文献   

7.
I examine the changing attitudes of Oskar Klein (1894–1977) and Albert Einstein (1879–1955) toward the notion of extending general relativity by an extra dimension with the aim of encompassing electromagnetism and gravitation in a unified field theory. I show how Klein developed his model of five-dimensional unification with the goal of explaining the discreteness of atomic energy levels, and how Einstein later embraced that goal. By examining the correspondence between Klein and Einstein, some of which was relayed through Paul Ehrenfest (1880–1933), I speculate that Klein’s work helped motivate Einstein to explore deterministic five-dimensional theories as a potential alternative to probabilistic quantum mechanics. Finally, I consider the contributions of Wolfgang Pauli (1900–1958) to the subject and elucidate his role in convincing Klein and Einstein that their models were not viable. Paul Halpern is Professor of Physics at the University of the Sciences in Philadelphia. He currently is a member of the Executive Committee of the Forum on the History of Physics of the American Physical Society.  相似文献   

8.
Luis Alvarez and colleagues discovered muon-catalyzed fusion of hydrogen isotopes by chance in late 1956. On sabbatical leave at Princeton University during that year, I read the first public announcement of the discovery at the end of December in that well-known scientific journal, The New York Times. A nuclear theorist by prior training, I was intrigued enough in the phenomenon to begin some calculations. I describe my work here, my interaction with Alvarez, and a summary of the surprising developments, both before and after Alvarez’s discovery. The rare proton–deuteron (p–d) fusion events in Alvarez’s liquid-hydrogen bubble chamber occurred only because of the natural presence of a tiny amount of deuterium (heavy hydrogen). Additionally, the fusion rate, once the proton–deuteron–muon (pdμ ) molecular ion has been formed, is sufficiently slow that only rarely does an additional catalytic act occur. A far different situation occurs for muons stopping in pure deuterium or a deuterium–tritium (dt) mixture where the fusion rates are many orders of magnitude larger and the molecular-formation rates are large compared to the muon’s decay rate. The intricate interplay of atomic, molecular, and nuclear science, together with highly fortuitous accidents in the molecular dynamics and the hope of practical application, breathed life into a seeming curiosity. A small but vigorous worldwide community has explored these myriad phenomena in the past 50 years.  相似文献   

9.
Horace Richard Crane (1907–2007) was born and educated in California. His childhood was full of activities that helped him become an outstanding experimental physicist. As a graduate student at the California Institute of Technology (1930–1934), he had the good fortune to work with Charles C. Lauritsen (1892–1968) just as he introduced accelerator-based nuclear physics to Caltech. They shared the euphoric excitement of opening up a new field with simple, ingenious apparatus and experiments. This work prepared Crane for his career at the University of Michigan (1935–1973) where in the 1950s, after making the first measurement of the electron’s magnetic moment, he devised the g−2 technique and made the first measurement of the anomaly in the electron’s magnetic moment. A man of direct, almost laconic style, he made lasting contributions to the exposition of physics to the general public and to its teaching in high schools, community colleges, four-year colleges, and universities. I tell how he became a physicist and describe some of his early achievements.  相似文献   

10.
I draw on my interviews in 2005–2007 with Gerson Goldhaber (1924–2010), his wife Judith, and his colleagues at Lawrence Berkeley National Laboratory. I discuss his childhood, early education, marriage to his first wife Sulamith (1923–1965), and his further education at the Hebrew University in Jerusalem (1942–1947) and his doctoral research at University of Wisconsin at Madison (1947–1950). He then was appointed to an instructorship in physics at Columbia University (1950–1953) before accepting a position in the physics department at the University of California at Berkeley and the Radiation Laboratory (later the Lawrence Berkeley Laboratory, today the Lawrence Berkeley National Laboratory), where he remained for the rest of his life. He made fundamental contributions to physics, including to the discovery of the antiproton in 1955, the GGLP effect in 1960, the psi particle in 1974, and charmed mesons in 1977, and to cosmology, including the discovery of the accelerating universe and dark energy in 1998. Beginning in the late 1960s, he also took up art, and he and his second wife Judith, whom he married in 1969, later collaborated in illustrating and writing two popular books. Goldhaber died in Berkeley, California, on July 19, 2010, at the age of 86.  相似文献   

11.
I provide a guide to Gdańsk (Danzig) and some of its suburbs, focusing on sites of particular interest to physicists. These include the Town Hall with the old Gdańsk standards of length at its entrance, the solar dial of 1588 on its corner, and its bell tower; the Naturalists Society; the medieval harbor crane; the medieval astronomical clock in St. Mary’s Church; the late nineteenth-century lighthouse and time ball; and sites associated with Nicolaus Copernicus (1473–1543), Johannes Hevelius (1611–1687), Daniel Gabriel Fahrenheit (1686–1736), and Daniel Gralath (1708–1767). I also comment on the history of and physical research being carried out today at the Technical University of Gdańsk and the University of Gdańsk.  相似文献   

12.
I first sketch the history of the German Physical Society (Deutsche Physikalische Gesellschaft,DPG) from its founding by six young Berlin scientists as the Physical Society of Berlin (Physikalische Gesellschaft zu Berlin) in 1845, through its renaming as the DPG in 1899 and its rise to prominence by the beginning of the 1930s. I then turn to the history of the DPG during the Third Reich, which can be divided into two periods, from the transfer of power in Germany to the Nazis in 1933 to 1940, and from 1941 to 1945. During the first period, Johannes Stark (1874–1957), one of the leaders of the “German Physics” (Deutsche Physik) movement, attempted to gain election as the Chairman of the DPG in September 1933 but was repulsed. A period of relative autonomy of the DPG from Nazi ideology and policies ensued, which gradually was transformed into one of accommodation, until at the end of the 1938, Peter Debye (1884–1966), then Chairman of the DPG, bowed to governmental demands and Nazi activists in the DPG, introduced Nazi principles, and strongly advised the Jewish members of the DPG to withdraw from it. Debye left Germany in early 1940, and after a transitional period in which Jonathan Zenneck (1871–1959) served as Acting Chairman, Carl Ramsauer (1879–1955) was elected Chairman of the DPG in December 1940, thus opening the second period, the Ramsauer era, which lasted from 1941 until the end of the war in 1945. Ramsauer oversaw the self-coordination (Selbstgleichschaltung) of the DPG to the Nazi regime, and as an industrial physicist he led the DPG to establish ever more alliances with powerful figures in the military-industrial complex of Nazi Germany, which worked to the advantage both of Ramsauer and the DPG and to that of the Nazi regime during the course of the war. Finally, as the military defeat of Germany loomed, Ramsauer took steps aimed at insuring the survival of German physics in the postwar period. After the war, he masked the wartime activities of himself and the DPG, thereby contributing to the postwar conspiracy of silence or minimization of the Nazi past in Germany. Dieter Hoffmann is a research scholar at the Max Planck Institute for the History of Science and a professor at Humboldt University in Berlin.  相似文献   

13.
This paper is based upon five interviews I conducted with Robert Vivian Pound in 2006–2007 and covers his childhood interest in radios, his time at the Massachusetts Institute of Technology Radiation Laboratory during the Second World War, his work on the discovery of nuclear magnetic resonance in condensed matter, his travels as a professor at Harvard University, and his social interactions with other physicists.  相似文献   

14.
Electronic-vibrational spectra of both imidazole (I) and the intermediate molecular structure (II) in the intramolecular proton transfer process N1H(I) → N3H(III) have been calculated and analyzed theoretically. The geometries of the molecular structures of I and II in the first ππ* excited state were determined using semi-empirical correlations and the method of hybridized atomic orbitals. The difference in their spectra indicates that the intramolecular proton-transfer mechanism with imidazole (I ↔ III) tautomeric conversion can be identified by electronic-vibrational spectroscopy. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 2, pp. 164–169, March–April, 2008.  相似文献   

15.
In the 1930s Ernest Rutherford (1871–1937) repeatedly suggested, sometimes angrily, that the possibility of harnessing atomic energy was “moonshine.” Yet, as war approached he secretly advised the British government to “keep an eye on the matter.” I suggest that Rutherford did not really believe his “moonshine” claim but did have profound reasons for making it. If I am correct, then this casts additional light on his personality, stature, and career.  相似文献   

16.
I trace the history of the physical and applied sciences, and particularly physics, in Glasgow. Among the notable individuals I discuss are Joseph Black (1728–1799), James Watt (1736–1819), William John Macquorn Rankine (1820–1872), William Thomson, Lord Kelvin (1824–1907), John Kerr (1824–1907), Frederick Soddy (1877–1956), John Logie Baird (1888–1946), and Ian Donald (1910–1987), as well as physics-related businesses.The locations, centering on the city center and University of Glasgow, include sites both recognizable today and transformed from past usage, as well as museums and archives related to the history and interpretation of physics.  相似文献   

17.
Quirino Majorana (1871–1957) was an outstanding Italian experimental physicist who investigated a wide range of phenomena during his long career in Rome,Turin, and Bologna. We focus on his experiments in Turin during 1916–1921 and in Bologna during 1921–1934 to test the validity of Albert Einstein’s postulate on the constancy of the speed of light and to detect gravitational absorption. These experiments required extraordinary skill, patience, and dedication, and all of them confirmed Einstein’s postulate and Isaac Newton’s law of universal gravitation to high precision. Had they not done so, Majorana’s fame among historians and physicists no doubt would be much greater than it is today. Giorgio Dragoni is Professor of History of Physics at the University of Bologna. Giulio Maltese is a Roman member of the Italian Society for the History of Physics and Astronomy. Luisa Atti is a Bolognese member of the Association for the Teaching of Physics.  相似文献   

18.
The analytical response of a fs/ns double-pulse laser induced breakdown spectroscopy technique based on the orthogonal reheating induced by a ns-laser pulse on a fs-laser ablation plume is presented. All investigations have been performed in air at atmospheric pressure and employing certified copper-based-alloy targets. The emission intensities of the considered electronic transitions of Pb(I), Sn(I) and Zn(I) have been normalised with a Cu(I) emission line intensity belonging to the same considered spectral range. Emission data, acquired with inter-pulse steps of 2 μs within the delay range of 1–200 μs, have shown that fractionation takes place. Nevertheless, excellent linear regression coefficients (0.998–0.999), despite the target’s large compositional variation and fractionation effects, have been obtained by integrating all emission intensity data along the whole inter-pulse delays used. Deviations from the theoretical ratio of the Zn(I)/Cu(I) emission intensities are shown and some hypotheses about the processes involved are formulated.  相似文献   

19.
The seven vesicular formulations CER(−), CER(+), CER(I), PC(−), PC(+), DAG(B) and DAG(I) have been developed using ceramide IIIB (CER), phosphatidylcholine (PC), or diacylglycerides (DAG) as main lipid components. B and I indicate the processed hydrophilic surfactant Brij 58 and Imwitor 375, (+) and (−) symbolize the positive and negative zeta potential. The influence of the bilayer microviscosity on the features of lipid vesicles as dermal drug delivery system is widely discussed, but comparable and reproducible results could not be found. For the measurement of the microviscosity by electron spin resonance the lipophilic spin probe of 14-doxylpalmitoylic acid methyl ester (DPME) was incorporated into the bilayer. Rotational correlation times (τc) between 0.3 and 1.8 ns were calculated. The dynamic viscosities (η) of eight different medium-chained triglycerides–castor oil mixtures in the range between 25 and 948 mPa · s, as well as the corresponding τc values of DPME in these mixtures, were determined to establish a calibration curve for the estimation of the microviscosity. The microviscosities of the vesicle membranes increase from 40 to 565 mPa · s in the following order DAG(B) = DAG(I) < PC(−) ≈ CER(I) < CER(−) ≤ CER(+) < PC(+). The microviscosity of 49.8 ± 2.5 mPa · s in pure unsaturated soy PC membranes decreases on adding the sodium cholate to 28.3–29.4 mPa · s, whereas the addition of dilauroylphosphatidylcholine in repeated freeze–thaw cycles or 8.5% ethanol in the hydrophilic phase had no influence. Authors' address: Hans-Hubert Borchert, Institute of Pharmacy, Free University of Berlin, Kelchstrasse 31, Berlin 12169, Germany  相似文献   

20.
The success of the moving puncture method for the numerical simulation of black hole systems can be partially explained by the properties of stationary solutions of the 1 + log coordinate condition. We compute stationary 1 + log slices of the Schwarzschild spacetime in isotropic coordinates in order to investigate the coordinate singularity that the numerical methods have to handle at the puncture. We present an alternative integration method to obtain isotropic coordinates that simplifies numerical integration and that gives direct access to a local expansion in the isotropic radius near the puncture. Numerical results have shown that certain quantities are well approximated by a function linear in the isotropic radius near the puncture, while here we show that in some cases the isotropic radius appears with an exponent that is close to but unequal to one. This paper is dedicated to the memory of Jürgen Ehlers. I have known JE for a number of years, in particular during his time as founding director of the Albert Einstein Institute in Potsdam. JE was the mentor of my habilitation thesis in 1996, and I am deeply thankful for many insightful discussions. JE combined great breadth and physical intuition with sharp analytical thought. His example inspired me to look beyond the numerical methods and results of numerical relativity to the analytic foundations. For example, while at the AEI, S. Brandt and I introduced “puncture initial data” for the numerical construction of general multiple black hole spacetimes [3]. While the puncture construction starts with an analytic trick of the sort that numerical relativists may devise, it is fair to say that the keen interest in analytical relativity created by JE at the AEI induced us to push our analysis one step further. As a result [3] connects to [26] for an existence and uniqueness proof for such black hole initial data, using weighted Sobolev spaces (see also [4–6]). The present work and its predecessors [9–12] represent an example where numerical experiments led to the discovery of an analytic solution for the 1 + log gauge for the Schwarzschild solution, and the present result, although modest, is of the type which I believe JE would have appreciated.  相似文献   

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