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Hendrik Antoon Lorentz's Struggle with Quantum Theory A. J
Hendrik Antoon Lorentz’s struggle with quantum theory A. J. Kox Archive for History of Exact Sciences ISSN 0003-9519 Volume 67 Number 2 Arch. Hist. Exact Sci. (2013) 67:149-170 DOI 10.1007/s00407-012-0107-8 1 23 Your article is published under the Creative Commons Attribution license which allows users to read, copy, distribute and make derivative works, as long as the author of the original work is cited. You may self- archive this article on your own website, an institutional repository or funder’s repository and make it publicly available immediately. 1 23 Arch. Hist. Exact Sci. (2013) 67:149–170 DOI 10.1007/s00407-012-0107-8 Hendrik Antoon Lorentz’s struggle with quantum theory A. J. Kox Received: 15 June 2012 / Published online: 24 July 2012 © The Author(s) 2012. This article is published with open access at Springerlink.com Abstract A historical overview is given of the contributions of Hendrik Antoon Lorentz in quantum theory. Although especially his early work is valuable, the main importance of Lorentz’s work lies in the conceptual clarifications he provided and in his critique of the foundations of quantum theory. 1 Introduction The Dutch physicist Hendrik Antoon Lorentz (1853–1928) is generally viewed as an icon of classical, nineteenth-century physics—indeed, as one of the last masters of that era. Thus, it may come as a bit of a surprise that he also made important contribu- tions to quantum theory, the quintessential non-classical twentieth-century develop- ment in physics. The importance of Lorentz’s work lies not so much in his concrete contributions to the actual physics—although some of his early work was ground- breaking—but rather in the conceptual clarifications he provided and his critique of the foundations and interpretations of the new ideas. -
Einstein's Washington Manuscript on Unified Field Theory
Einstein’s Washington Manuscript on Unified Field Theory Tilman Sauer∗ and Tobias Schütz† Institute of Mathematics Johannes Gutenberg University Mainz D-55099 Mainz, Germany Version of August 25, 2020 Abstract In this note, we point attention to and briefly discuss a curious manu- script of Einstein, composed in 1938 and entitled “Unified Field Theory,” the only such writing, published or unpublished, carrying this title without any further specification. Apparently never intended for publication, the manuscript sheds light both on Einstein’s modus operandi as well as on the public role of Einstein’s later work on a unified field theory of gravitation and electromagnetism. arXiv:2008.10005v1 [physics.hist-ph] 23 Aug 2020 ∗[email protected] †[email protected] 1 1 The “Washington manuscript” In July 1938, the Princeton based journal Annals of Mathematics published a paper On a Generalization of Kaluza’s Theory of Electricity in its Vol. 39, issue No. 3 (Einstein and Bergmann, 1938). The paper was co-authored by Albert Einstein (1879–1955) and his then assistant Peter Gabriel Bergmann (1915– 2002). It presented a new discussion of an approach toward a unified theory of the gravitational and electromagnetic fields based on an extension of the number of physical dimensions characterizing space-time. Such five-dimensional theories had been discussed already a number of times, notably by Theodor Kaluza in 1921, and then again in the late twenties by Oskar Klein and others (Goenner, 2004). Einstein had contributed to the discussion already in 1923 and in 1927, but had given up the approach in favor of another one based on distant parallelism (Sauer, 2014). -
Einstein's Equations for Spin $2 $ Mass $0 $ from Noether's Converse
Einstein’s Equations for Spin 2 Mass 0 from Noether’s Converse Hilbertian Assertion November 9, 2016 J. Brian Pitts Faculty of Philosophy, University of Cambridge [email protected] forthcoming in Studies in History and Philosophy of Modern Physics Abstract An overlap between the general relativist and particle physicist views of Einstein gravity is uncovered. Noether’s 1918 paper developed Hilbert’s and Klein’s reflections on the conservation laws. Energy-momentum is just a term proportional to the field equations and a “curl” term with identically zero divergence. Noether proved a converse “Hilbertian assertion”: such “improper” conservation laws imply a generally covariant action. Later and independently, particle physicists derived the nonlinear Einstein equations as- suming the absence of negative-energy degrees of freedom (“ghosts”) for stability, along with universal coupling: all energy-momentum including gravity’s serves as a source for gravity. Those assumptions (all but) imply (for 0 graviton mass) that the energy-momentum is only a term proportional to the field equations and a symmetric curl, which implies the coalescence of the flat background geometry and the gravitational potential into an effective curved geometry. The flat metric, though useful in Rosenfeld’s stress-energy definition, disappears from the field equations. Thus the particle physics derivation uses a reinvented Noetherian converse Hilbertian assertion in Rosenfeld-tinged form. The Rosenfeld stress-energy is identically the canonical stress-energy plus a Belinfante curl and terms proportional to the field equations, so the flat metric is only a convenient mathematical trick without ontological commitment. Neither generalized relativity of motion, nor the identity of gravity and inertia, nor substantive general covariance is assumed. -
Philosophical Rhetoric in Early Quantum Mechanics, 1925-1927
b1043_Chapter-2.4.qxd 1/27/2011 7:30 PM Page 319 b1043 Quantum Mechanics and Weimar Culture FA 319 Philosophical Rhetoric in Early Quantum Mechanics 1925–27: High Principles, Cultural Values and Professional Anxieties Alexei Kojevnikov* ‘I look on most general reasoning in science as [an] opportunistic (success- or unsuccessful) relationship between conceptions more or less defined by other conception[s] and helping us to overlook [danicism for “survey”] things.’ Niels Bohr (1919)1 This paper considers the role played by philosophical conceptions in the process of the development of quantum mechanics, 1925–1927, and analyses stances taken by key participants on four main issues of the controversy (Anschaulichkeit, quantum discontinuity, the wave-particle dilemma and causality). Social and cultural values and anxieties at the time of general crisis, as identified by Paul Forman, strongly affected the language of the debate. At the same time, individual philosophical positions presented as strongly-held principles were in fact flexible and sometimes reversible to almost their opposites. One can understand the dynamics of rhetorical shifts and changing strategies, if one considers interpretational debates as a way * Department of History, University of British Columbia, 1873 East Mall, Vancouver, British Columbia, Canada V6T 1Z1; [email protected]. The following abbreviations are used: AHQP, Archive for History of Quantum Physics, NBA, Copenhagen; AP, Annalen der Physik; HSPS, Historical Studies in the Physical Sciences; NBA, Niels Bohr Archive, Niels Bohr Institute, Copenhagen; NW, Die Naturwissenschaften; PWB, Wolfgang Pauli, Wissenschaftlicher Briefwechsel mit Bohr, Einstein, Heisenberg a.o., Band I: 1919–1929, ed. A. Hermann, K.V. -
Von Richthofen, Einstein and the AGA Estimating Achievement from Fame
Von Richthofen, Einstein and the AGA Estimating achievement from fame Every schoolboy has heard of Einstein; fewer have heard of Antoine Becquerel; almost nobody has heard of Nils Dalén. Yet they all won Nobel Prizes for Physics. Can we gauge a scientist’s achievements by his or her fame? If so, how? And how do fighter pilots help? Mikhail Simkin and Vwani Roychowdhury look for the linkages. “It was a famous victory.” We instinctively rank the had published. However, in 2001–2002 popular French achievements of great men and women by how famous TV presenters Igor and Grichka Bogdanoff published they are. But is instinct enough? And how exactly does a great man’s fame relate to the greatness of his achieve- ment? Some achievements are easy to quantify. Such is the case with fighter pilots of the First World War. Their achievements can be easily measured and ranked, in terms of their victories – the number of enemy planes they shot down. These aces achieved varying degrees of fame, which have lasted down to the internet age. A few years ago we compared1 the fame of First World War fighter pilot aces (measured in Google hits) with their achievement (measured in victories); and we found that We can estimate fame grows exponentially with achievement. fame from Google; Is the same true in other areas of excellence? Bagrow et al. have studied the relationship between can this tell us 2 achievement and fame for physicists . The relationship Manfred von Richthofen (in cockpit) with members of his so- about actual they found was linear. -
Science Fiction and Astronomy
Sci Fi Science Fiction and Astronomy Many science fiction books include subjects of astronomical interest. Here is a list of some that have been recommended to me or I’ve read. I expect that most are not in the University library but many are available in Kindle and other e-formats. At the top of my list is a URL to a much longer list by Andrew Fraknoi of the Astronomical Society of the Pacific. Each title in his list has a very brief summary indicating the kind of story it is. Andrew Fraknoi’s list (http://www.astrosociety.org/education/resources/scifi.html). Gregory Benford is a plasma physicist who has been rated by some as one of the finest observes and interpreters of science in modern fiction. Note: Timescape [Vista, ISBN 0575600500] In the Ocean of Night [Vista, ISBN 0575600357] Across the Sea of Suns [Vista, ISBN 0575600551] Great Sky River [Gallancy, ISBN 0575058315] Eater and over 2 dozen more available as e-books. Stephen Baxter Titan [Voyager, 1997, ISBN 0002254247] has been strongly recommended by New Scientist as a tense, near future, thriller you shouldn’t miss. David Brin has a PhD in astrophysics with which he brings real understanding of the Universe to his stories. The Crystal Spheres won an award. Fred Hoyle is probably the most famous astronomer to have written science fiction. The Back Cloud [Macmillan, ISBN 0333556011] is his classic, followed by A for Andromeda. Try also October the First is too late. Larry Niven’s stories include plenty of ideas inspired by modern astronomy. -
Einstein's Life and Legacy
Reflections Einstein's Life and Legacy Introduction Albert Einstein is the most luminous scientist of the past century, and ranks with Isaac Newton as one among the greatest physicists of all time. There is an enormous amount of material to choose from in talking about Einstein. He is without doubt also the most written about scientist of the past century, may be of all time. The Einstein Archives contain about 43,000 documents, and so far as I know the "Collected Papers of Albert Einstein" have only come upto 1917 with Volume 8 in English translation; another 32 volumes remain to be produced. In the face of all this, this account must be severely selective, and coherent as well. Einstein's life was incredibly rich and intense in the intellectual sense. This will become clear as I go along. In any case let me begin by presenting in Box 1 a brieflisting of a few important dates in his life, howsoever inadequate it may be. He was scientifically active essentially from 1902 upto 1935 at the highest imaginable levels, thus for more than three decades. The Miraculous Year Now let us turn to technical matters. First, a brief mention of his creative outburst of 1905, whose centenary we are celebrating this year. There were four fundamental papers, and the doctoral thesis, all in the six months from March to September. The first paper on the light quantum concept and explanation of the photo electric effect was submitted to Annalen der Physik in March; the second on Brownian Motion in May; and the third setting out the Special Theory of Relativity in June. -
Essays on Einstein's Science And
MAX-PLANCK-INSTITUT FÜR WISSENSCHAFTSGESCHICHTE Max Planck Institute for the History of Science PREPRINT 63 (1997) Giuseppe Castagnetti, Hubert Goenner, Jürgen Renn, Tilman Sauer, and Britta Scheideler Foundation in Disarray: Essays on Einstein’s Science and Politics in the Berlin Years ISSN 0948-9444 PREFACE This collection of essays is based on a series of talks given at the Boston Colloquium for Philosophy of Science, March 3 – 4, 1997, under the title “Einstein in Berlin: The First Ten Years.“ The meeting was organized by the Center for Philosophy and History of Science at Boston University and the Collected Papers of Albert Einstein, and co-sponsored by the Max Planck Institute for the History of Science. Although the three essays do not directly build upon one another, we have nevertheless decided to present them in a single preprint for two reasons. First, they result from a project that grew out of an earlier cooperation inaugurated by the Berlin Working Group “Albert Einstein.“ This group was part of the research center “Development and Socialization“ under the direction of Wolfgang Edel- stein at the Max Planck Institute for Human Development and Education.1 The Berlin Working Group, directed by Peter Damerow and Jürgen Renn, was sponsored by the Senate of Berlin. Its aim was to pursue research on Einstein in Berlin with particular attention to the relation between his science and its context. The research activities of the Working Group are now being continued at the Max Planck Institute for the History of Science partly, in cooperation with Michel Janssen, John Norton, and John Stachel. -
Einstein, Nordström and the Early Demise of Scalar, Lorentz Covariant Theories of Gravitation
JOHN D. NORTON EINSTEIN, NORDSTRÖM AND THE EARLY DEMISE OF SCALAR, LORENTZ COVARIANT THEORIES OF GRAVITATION 1. INTRODUCTION The advent of the special theory of relativity in 1905 brought many problems for the physics community. One, it seemed, would not be a great source of trouble. It was the problem of reconciling Newtonian gravitation theory with the new theory of space and time. Indeed it seemed that Newtonian theory could be rendered compatible with special relativity by any number of small modifications, each of which would be unlikely to lead to any significant deviations from the empirically testable conse- quences of Newtonian theory.1 Einstein’s response to this problem is now legend. He decided almost immediately to abandon the search for a Lorentz covariant gravitation theory, for he had failed to construct such a theory that was compatible with the equality of inertial and gravitational mass. Positing what he later called the principle of equivalence, he decided that gravitation theory held the key to repairing what he perceived as the defect of the special theory of relativity—its relativity principle failed to apply to accelerated motion. He advanced a novel gravitation theory in which the gravitational potential was the now variable speed of light and in which special relativity held only as a limiting case. It is almost impossible for modern readers to view this story with their vision unclouded by the knowledge that Einstein’s fantastic 1907 speculations would lead to his greatest scientific success, the general theory of relativity. Yet, as we shall see, in 1 In the historical period under consideration, there was no single label for a gravitation theory compat- ible with special relativity. -
Natural Selection and Coalescent Theory
Natural Selection and Coalescent Theory John Wakeley Harvard University INTRODUCTION The story of population genetics begins with the publication of Darwin’s Origin of Species and the tension which followed concerning the nature of inheritance. Today, workers in this field aim to understand the forces that produce and maintain genetic variation within and between species. For this we use the most direct kind of genetic data: DNA sequences, even entire genomes. Our “Great Obsession” with explaining genetic variation (Gillespie, 2004a) can be traced back to Darwin’s recognition that natural selection can occur only if individuals of a species vary, and this variation is heritable. Darwin might have been surprised that the importance of natural selection in shaping variation at the molecular level would be de-emphasized, beginning in the late 1960s, by scientists who readily accepted the fact and importance of his theory (Kimura, 1983). The motivation behind this chapter is the possible demise of this Neutral Theory of Molecular Evolution, which a growing number of population geneticists feel must follow recent observations of genetic variation within and between species. One hundred fifty years after the publication of the Origin, we are struggling to fully incorporate natural selection into the modern, genealogical models of population genetics. The main goal of this chapter is to present the mathematical models that have been used to describe the effects of positive selective sweeps on genetic variation, as mediated by gene genealogies, or coalescent trees. Background material, comprised of population genetic theory and simulation results, is provided in order to facilitate an understanding of these models. -
Berlin Period Reports on Albert Einstein's Einstein's FBI File –
Appendix Einstein’s FBI file – reports on Albert Einstein’s Berlin period 322 Appendix German archives are not the only place where Einstein dossiers can be found. Leaving aside other countries, at least one personal dossier exists in the USA: the Einstein File of the Federal Bureau of Investigation (FBI).1036 This file holds 1,427 pages. In our context the numerous reports about Ein- stein’s “Berlin period” are of particular interest. Taking a closer look at them does not lead us beyond the scope of this book. On the contrary, these reports give a complex picture of Einstein’s political activities during his Berlin period – albeit from a very specific point of view: the view of the American CIC (Counter Intelligence Corps) and the FBI of the first half of the 1950s. The core of these reports is the allegation that Einstein had cooperated with the communists and that his address (or “office”) had been used from 1929 to 1932 as a relay point for messages by the CPG (Communist Party of Germany, KPD), the Communist International and the Soviet Secret Service. The ultimate aim of these investigations was, reportedly, to revoke Einstein’s United States citizenship and banish him. Space constraints prevent a complete review of the individual reports here. Sounderthegivencircumstancesasurveyofthecontentsofthetwomost im- portant reports will have to suffice for our purposes along with some additional information. These reports are dated 13 March 1950 and 25 January 1951. 13 March 1950 The first comprehensive report by the CIC (Hq. 66th CIC Detachment)1037 about Einstein’s complicity in activities by the CPG and the Soviet Secret Service be- tween 1929 and 1932 is dated 13 March 1950.1038 Army General Staff only submit- ted this letter to the FBI on 7 September 1950. -
Science Fiction Stories with Good Astronomy & Physics
Science Fiction Stories with Good Astronomy & Physics: A Topical Index Compiled by Andrew Fraknoi (U. of San Francisco, Fromm Institute) Version 7 (2019) © copyright 2019 by Andrew Fraknoi. All rights reserved. Permission to use for any non-profit educational purpose, such as distribution in a classroom, is hereby granted. For any other use, please contact the author. (e-mail: fraknoi {at} fhda {dot} edu) This is a selective list of some short stories and novels that use reasonably accurate science and can be used for teaching or reinforcing astronomy or physics concepts. The titles of short stories are given in quotation marks; only short stories that have been published in book form or are available free on the Web are included. While one book source is given for each short story, note that some of the stories can be found in other collections as well. (See the Internet Speculative Fiction Database, cited at the end, for an easy way to find all the places a particular story has been published.) The author welcomes suggestions for additions to this list, especially if your favorite story with good science is left out. Gregory Benford Octavia Butler Geoff Landis J. Craig Wheeler TOPICS COVERED: Anti-matter Light & Radiation Solar System Archaeoastronomy Mars Space Flight Asteroids Mercury Space Travel Astronomers Meteorites Star Clusters Black Holes Moon Stars Comets Neptune Sun Cosmology Neutrinos Supernovae Dark Matter Neutron Stars Telescopes Exoplanets Physics, Particle Thermodynamics Galaxies Pluto Time Galaxy, The Quantum Mechanics Uranus Gravitational Lenses Quasars Venus Impacts Relativity, Special Interstellar Matter Saturn (and its Moons) Story Collections Jupiter (and its Moons) Science (in general) Life Elsewhere SETI Useful Websites 1 Anti-matter Davies, Paul Fireball.