Felix EHRENHAFT Magnetic Current
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Chronological List of Correspondence, 1895–1920
CHRONOLOGICAL LIST OF CORRESPONDENCE, 1895–1920 In this chronological list of correspondence, the volume and document numbers follow each name. Documents abstracted in the calendars are listed in the Alphabetical List of Texts in this volume. 1895 13 or 20 Mar To Mileva Maric;;, 1, 45 29 Apr To Rosa Winteler, 1, 46 Summer To Caesar Koch, 1, 6 18 May To Rosa Winteler, 1, 47 28 Jul To Julia Niggli, 1, 48 Aug To Rosa Winteler, 5: Vol. 1, 48a 1896 early Aug To Mileva Maric;;, 1, 50 6? Aug To Julia Niggli, 1, 51 21 Apr To Marie Winteler, with a 10? Aug To Mileva Maric;;, 1, 52 postscript by Pauline Einstein, after 10 Aug–before 10 Sep 1,18 From Mileva Maric;;, 1, 53 7 Sep To the Department of Education, 10 Sep To Mileva Maric;;, 1, 54 Canton of Aargau, 1, 20 11 Sep To Julia Niggli, 1, 55 4–25 Nov From Marie Winteler, 1, 29 11 Sep To Pauline Winteler, 1, 56 30 Nov From Marie Winteler, 1, 30 28? Sep To Mileva Maric;;, 1, 57 10 Oct To Mileva Maric;;, 1, 58 1897 19 Oct To the Swiss Federal Council, 1, 60 May? To Pauline Winteler, 1, 34 1900 21 May To Pauline Winteler, 5: Vol. 1, 34a 7 Jun To Pauline Winteler, 1, 35 ? From Mileva Maric;;, 1, 61 after 20 Oct From Mileva Maric;;, 1, 36 28 Feb To the Swiss Department of Foreign Affairs, 1, 62 1898 26 Jun To the Zurich City Council, 1, 65 29? Jul To Mileva Maric;;, 1, 68 ? To Maja Einstein, 1, 38 1 Aug To Mileva Maric;;, 1, 69 2 Jan To Mileva Maric;; [envelope only], 1 6 Aug To Mileva Maric;;, 1, 70 13 Jan To Maja Einstein, 8: Vol. -
In Defense of Robert Andrews Millikan by David Goodstein
30 ENGINEERING & SCIENCE NO. 4 He also has been accused of male chauvinism, anti-Semitism, mistreating his graduate students, and, worst of all, scientific fraud. In Defense of Robert Andrews Millikan by David Goodstein Robert Andrews Millikan was the founder, first Thomson and his colleagues tried to do it by leader, first Nobel Prize winner and all-around observing how an applied electric field changed patron saint of the California Institute of Technol- the rate of gravitational fall of clouds of water ogy, an institution that has given me employment droplets that had nucleated on ions in a cloud for more years than I care to remember. He also chamber. The upper edge of the cloud, which had has been accused of male chauvinism, anti- the smallest droplets, could be assumed to contain Semitism, mistreating his graduate students, and, single charges. In this way, a crude but correct worst of all, scientific fraud. Since we at Caltech estimate of the unit of electric charge could be feel a solemn duty to defend our hero, my purpose obtained. These cloud-chamber experiments were Isaac Newton (framed) and here is to tell his story, look into these various the starting point of Millikan’s efforts. accusations, and, to the extent that I can, mount Working with a graduate student named Louis Robert Millikan: colleagues a defense for Professor Millikan. Begeman, Millikan had the idea of applying a in crime? Speaking of Millikan was born in 1868, son of a Midwestern much stronger electric field than had previously crime, the Newton portrait minister. -
A Debate on Magnetic Current: the Troubled Einstein–Ehrenhaft Correspondence
BJHS 44(3): 371–400, September 2011. © British Society for the History of Science 2010 doi:10.1017/S0007087410001299 First published online 8 October 2010 A debate on magnetic current: the troubled Einstein–Ehrenhaft correspondence GILDO MAGALHÃES SANTOS* Abstract. The unconventional correspondence between physicists Albert Einstein and Felix Ehrenhaft, especially at the height of the alleged production by the latter of magnetic monopoles, is examined in the following paper. Almost unknown by the general public, it is sometimes witty, yet it can be pathetic, and certainly bewildering. At one point the arguments they exchanged became a poetic duel between Einstein and Ehrenhaft’s wife. Ignored by conventional Einstein biographies, this episode took place during the initial years of the Second World War, but was rooted in disputes dating back to the early years of the twentieth century. The interesting intersection of a series of scientific controversies also highlights some aspects of the personal dramas involved, and after so many years the whole affair in itself is still intriguing. The issues in the Ehrenhaft–Einstein epistolary Science has now practically forgotten the polemic figure of Felix Albert Ehrenhaft (1879–1952), an Austrian physicist who in the 1900s and 1910s assumed the existence of electric charges smaller than the electron, based on his experimental work. Three decades later, Ehrenhaft came up with what appeared to be another heresy, insisting that he had observed isolated magnetic poles. He maintained a correspondence with Albert Einstein on these subjects for about thirty years, trying to convince Einstein of the validity of his arguments, while Einstein attacked Ehrenhaft’s conclusions, but followed his experimental work. -
Geophysical Abstracts 139 October-December 1949
Geophysical Abstracts 139 October-December 1949 (Numbers 11442-11678) By MARY C. RABBITT, V. L. SKITSKY, and S. T. VESSELOWSKY G E O L O G I C A L S U R V E Y BULLETIN 966-D Abstracts of world literature contained in periodicals, books, a^kd-patents UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1950 UNITED STATES DEPARTMENT OF THE INTERIOR Oscar L. Chapman, Secretary GEOLOGICAL SURVEY W. E. Wrather, Director '" For sale by; the Superintendent of Documents, U. S. Government Printing Office, Washington ','j :; ? 25, D.;,C.V Price.25;cents, (pkper Coyer). The printing of this publication has been approved by the Director of the Bureau of the Budget, February 1948. CONTENTS Page Introduction. _____--____-_--______-__-___-_-_.._______________..____ 253 0. General geophysical subjects.___________________________________ 254 1. Gravitational methods________________________________________ 257 2. Magnetic methods_____________________________________________ 263: 3. Seismic methods_______________-_-________-_-___.______________ 272 4. Electrical methods_______._____________________________________ 288: 5. Radioactive methods.__________________________________________ 290' 6. Geothermal methods.__________________________________________ 298' 7. Geochemical methods________________________________________ 299 8. Drill-hole methods.._.___.._________________._______ 300' 9. Unclassified geophysical subjects.__-__---____-__-________--______ 304 10. Related geological subjects.___________________'__________________ 308 11. Technical aids to exploration......._____________________________ 313 12. Patents..-.---.--------.----------.--------------------------. 315 -_-__---_---_------_-__-_-___-_----__.-____--_-____-_.-.__ 331 in GEOPHYSICAL ABSTRACTS 139, OCTOBER-DECEMBER 1949 By MARY C. RABBITT, V. L. SKITSKY, and S. T. VESSELOWSKY INTRODUCTION . Geophysical Abstracts are compiled by the Geophysics Branch of the Geological Survey, United States Department of the Interior, as an aid to those engaged in geophysical research and exploration. -
On the Art of Scientific Imagination
On the Art of Scientific Imagination The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Holton, Gerald. 1996. On the Art of Scientific Imagination. Daedalus 125 (2): 183-208. Published Version https://www.jstor.org/stable/20013446? seq=1#metadata_info_tab_contents Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:40508269 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA NOTES FROM THE ACADEMY The text of addresses given at the Stated Meetings of the American Academy of Arts and Sciences are generally printed in the Academy's Bulletin, distributed principally to Fellows and Foreign Honorary Members of the Academy. Because the Bulletin's format is not one designed to accommodate many detailed illustrations, and because the communication delivered by Professor Gerald Holton at the House of the Academy, like others recently given, raised such interest among those who heard it, a decision was made to make it more widely available through publication in the Academy's journal, Dadalus. This practice, followed very occasionally in the past, has much to recommend it and may be pursued more fre quently in the future. [S.R.G.] Gerald Holton On the Art of Scientific Imagination Wver HEN THE ACADEMY S PRESIDENT asked if I would speak on Saint Valentine's Day, I gladly accepted the honor. -
Othmar Preining 28 June 1927 – 26 September 2007
Othmar Preining 28 June 1927 – 26 September 2007 Professor Dr. Othmar Preining died on September 26, 2007. He taught 28 years at the University of Vienna; numerous students attended his lectures. He tried to educate them not only in basic physics, but also to look for the essential and to see the interrelations. He had many PhD and master students. Six of his co-workers obtained a habilitation under his guidance. His main research area was aerosol science but he was always interested and well informed in all fields of science. In this way, he stimulated ground-breaking work and led science in new directions. He was co-founder of Gesellschaft für Aerosolforschung (GAeF, Association for Aerosol Research), the first international aerosol association in the world. Othmar Preining was born in Vienna on June 28, 1927. He also attended school in Vienna. Before his school education ended, the Second World War was in full progress, drastically degrading the quality of education. Moreover he was seriously ill and missed almost a full year due to frequent hospitalization. His bad health did not allow for any kind of sport. But Othmar Preining made the best of it, devoting his time to natural sciences. He attended public lectures and bought scientific books. Thus he acquired knowledge that most students in their first years did not have. He finished grammar school with honors and studied mathematics, physics and astronomy at the University of Vienna. He was deeply impressed by Physicist Felix Ehrenhaft. Preining attended all of Ehrenhaft’s lectures and seminars and later became his doctoral student, even though he also got offers to do his PhD with famous professors of theoretical physics. -
Karl Przibram: Radioactivity, Crystals, and Colors
Phys. Perspect. 21 (2019) 163–193 Ó 2019 The Author(s) This article is an open access publication 1422-6944/19/030163-31 https://doi.org/10.1007/s00016-019-00242-z Physics in Perspective Karl Przibram: Radioactivity, Crystals, and Colors Wolfgang L. Reiter* Karl Przibram is one of the pioneers of early solid state physics in the field of the inter- dependence of coloration effects and luminescence in solids (crystals, minerals) induced by radiation. In 1921 Przibram discovered the effect of radio-photoluminescence, the light- stimulated phosphorescence in activated crystals induced by gamma rays. In 1926 Przibram was the first to use the term, Farbzentrum (color center, F-center), and in 1923 he advanced the view of atomic centers as carriers of coloration. Being a pupil of Ludwig Boltzmann and Franz S. Exner, he dedicated his early work to condensation and conductivity phenomena in gases and Brownian motion. Under the influence of Stefan Meyer, he began his lifelong interest in mineralogy, setting up his own research group at the Vienna Radium Institute, which pioneered investigations on thermoluminescence and gave a first description of glow curves. Being of Jewish descent, Przibram had to leave Austria after the Nazis took power; he found shelter in Belgium and returned to Austria in 1946 as professor for experimental physics at the University of Vienna. This paper is a first attempt to give an overview of the cultural and scientific background of Przibram’s life and science in context of the cultural and political developments from 1900 to 1950 in Austria. Key words: Biography; mineral physics; coloration effects and luminescence in solids; Ludwig Boltzmann; Franz S. -
604. E. B.: Albert Einstein and Austria, Austria Today 4/1979, 40
604. E. B.: Albert Einstein and Austria, Austria Today 4/1979, 40. AIABERT EINSTEIN AND AUSTRIA by Engelbert Broda n 1979, a hundred years after his Niels Bohr - also birth, the greatest scientist o( our one of Einstein's I time, Albert Einstein, has been great friends, celebrated m many countries. In however. Ein- Austria it has been recalled that stein feIt a deep Einstein had many dose ties with our affection for country; both on the level of ideas and Hans Thirring that cf personal relationships. of Vienna, as a While Einstein was still an result of the unknown "expert 3rd dass" in the latter's contribu- Swiss patent office, he was under the tion to the speIl of two Austrian physicists. They Theory of Rel- were both alive then, but they had ativity and also never heard of Einstein. Their his upright re- thoughts were to accompany hirn all sistance against his life. warrnongers and One of them· was Ernst Mach, of Nazis. Graz, Prague and Vienna Universities, Einstein's re- an experimental physicist who also had lationship with an intense interest in sense physiology, Einstein in Vienna (J 93]) the Adler family in the history of science and in was also re- philosophy. Mach's criticism of markable. In dogmatic ideas gready helped Einstein uniform. When his litde son, Hans Zutich, he became friends with his in formulating his trail-blazing Theory Albert, asked hirn to go out in the colleague Friedrich Adler, the son of of Relativity in 1905, one of the pillars uniform, Einstein replied, "But people the undisputed leader of the Austrian of modern physics. -
In Defense of Robert Andrews Millikan by David Goodstein
30 ENGINEERING & SCIENCE NO. 4 He also has been accused of male chauvinism, anti-Semitism, mistreating his graduate students, and, worst of all, scientific fraud. In Defense of Robert Andrews Millikan by David Goodstein Robert Andrews Millikan was the founder, first Thomson and his colleagues tried to do it by leader, first Nobel Prize winner and all-around observing how an applied electric field changed patron saint of the California Institute of Technol- the rate of gravitational fall of clouds of water ogy, an institution that has given me employment droplets that had nucleated on ions in a cloud for more years than I care to remember. He also chamber. The upper edge of the cloud, which had has been accused of male chauvinism, anti- the smallest droplets, could be assumed to contain Semitism, mistreating his graduate students, and, single charges. In this way, a crude but correct worst of all, scientific fraud. Since we at Caltech estimate of the unit of electric charge could be feel a solemn duty to defend our hero, my purpose obtained. These cloud-chamber experiments were Isaac Newton (framed) and here is to tell his story, look into these various the starting point of Millikan’s efforts. accusations, and, to the extent that I can, mount Working with a graduate student named Louis Robert Millikan: colleagues a defense for Professor Millikan. Begeman, Millikan had the idea of applying a in crime? Speaking of Millikan was born in 1868, son of a Midwestern much stronger electric field than had previously crime, the Newton portrait minister. -
The Concept of Velocity in the History of Brownian Motion from Physics to Mathematics and Vice Versa
The concept of velocity in the history of Brownian motion From physics to mathematics and vice versa Arthur Genthon1,* 1Gulliver, ESPCI Paris, PSL University, CNRS, 75005 Paris, France *[email protected] Brownian motion is a complex object shared by different communities: first ob- served by the botanist Robert Brown in 1827, then theorised by physicists in the 1900s, and eventually modelled by mathematicians from the 1920s. Consequently, it is now ambiguously referring to the natural phenomenon but also to the theo- ries accounting for it. There is no published work telling its entire history from its discovery until today, but rather partial histories either from 1827 to Perrin's exper- iments in the late 1900s, from a physicist's point of view; or from the 1920s from a mathematician's point of view. In this article, we tackle a period straddling the two `half-histories' just mentioned, in order to highlight its continuity, to question the relationship between physics and mathematics, and to remove the ambiguities mentioned above. We study the works of Einstein, Smoluchowski, Langevin, Wiener, Ornstein and Uhlenbeck from 1905 to 1934 as well as experimental results, through the concept of Brownian velocity. We show how Brownian motion became a research topic for the mathematician Wiener in the 1920s, why his model was an idealization of physical reality, what Ornstein and Uhlenbeck added to Einstein's results and how Wiener, Ornstein and Uhlenbeck developed in parallel contradictory theories concerning Brownian velocity. 1. Introduction Brownian motion is in the first place a natural phenomenon, observed by the Scottish botanist Robert Brown in 1827. -
Einstein's Invention of Brownian Motion
Ann. Phys. (Leipzig) 14, Supplement, 23–37 (2005) / DOI 10.1002/andp.200410131 Einstein’s invention of Brownian motion J¨urgen Renn∗ Max-Planck-Institut f¨ur Wissenschaftsgeschichte, Wilhelmstr. 44, 10117 Berlin, Germany Published online 14 February 2005 Key words Brownian motion, kinetic theory of heat, statistical physics, stochastic processes, thermody- namics of solutions PACS 05.40.Jc, 05.20.Dd, 05.40.-a, 82.60.Lf The atomistic revolution1 The impact of Einstein’s work Einstein’s 1905 paper on Brownian motion was an essential contribution to the foundation of modern atomism [20]. Atomism as understood in science today presupposes, like its predecessor rooted in the theories of nature from Greek antiquity and from early modern times, that matter is constituted by small entities. But it no longer assumes that the properties and the behavior of these entities can simply be inferred from the familiar physical laws governing our macroscopic environment, nor that a description of matter in terms of its atomistic constituents can be exhaustive. Einstein succeeded in interpreting the irregular movements of small particles suspended in a liquid as visible evidence for the molecular motions constituting the heat of a ponderable body according to the kinetic theory of heat. But he did so by radically changing the understanding of these irregular motions which he no longer conceived as being characterized by a velocity in the classical sense but as a stochastic process that can only be described with the help of statistical methods. It is therefore not surprising that Einstein’s work on Brownian motion also became one of the pillars of modern statistical thermodynamics and, more generally, of the physics of stochastic processes. -
100 Years of the Theory of Brownian Motion
The Global and the Local: The History of Science and the Cultural Integration of Europe. nd Proceedings of the 2 ICESHS (Cracow, Poland, September 6–9, 2006) / Ed. by M. Kokowski. W. Gerhard Pohl * The theory of Brownian motion — one hundred years old ROBERT BROWN (1773–1858) discovered the phenomenon named after him in 1827.1 He as a botanist studied pollen grains under the microscope and was probably angry that these small particles moved around, and could not be studied well. He soon found out that not only pollen grains but all sorts of small particles showed this irregular motion. Since no energy was supplied from outside the movement was apparently supported from internal energy, which could only be thermal energy. Since the mid-nineteenth century several authors considered the kinetic theory of heat, developed by Clausius, Maxwell, Boltzmann and others, as a possible explanation of Brownian motion. But the potential complexity of the phenomenon was the main reason why it failed to become a key subject of the great works on the kinetic theory of heat. Since the 1870s several scientists pursued the idea that Brownian motion might be explained as the result of collisions between suspended particles and the molecules of the liquid. One of them was Siegmund Exner (1846–1926) a Viennese physiologist who published his observations in 1867.2 He found that the motion stopped at low temperatures and increased with increasing temperature. The motion also depended on the viscosity of the solution (in glycerine e.g. it stopped completely). In 1900 Siegmund Exner’s son the physicist Felix Maria Exner (1876– 1930), who later became a famous meteorologist, continued the studies of his father.3 He studied rubber- emulsions, and determined the velocity of particles with a diameter of 0.001 mm and smaller.