User:Guy Vandegrift/Timeline of Quantum Mechanics (Abridged)
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“Revista Istorică”, XXVIII, 2017, Nos. 1-2
“Revista istorică”, XXVIII, 2017, nos. 1-2 ABSTRACTS THE ARABS AND THE MONGOLS EXPANDING: A COMPARISON OF THE PREMISES VIRGIL CIOCÎLTAN The route from the nomad’s tent to the imperial palace had the same starting ground, namely the disadvantaged areas, which made their nomadic inhabitants particularly receptive to material gains, and the same finality: expansion and the formation of the two empires. Beyond the specific means of achieving each course individually, their essence was identical: the politic and social instability, which was endemic to the gentile societies of pre-Islamic Arabia and Mongolia before the rule of Genghis Khan, was removed by the great social and political renewals of the 7th, respectively the 12th century, which presented the nomadic inhabitants with a new identity, granted them social homogeneity and integrated them into state structures which superseded the traditional tribal entities. As the conscience of being Moslem transgressed the narrow gentile differences and allowed the formation of the great Islamic community (umma), composed of equal elements, at least in theory, which were unified precisely by the common faith in Allah, so Genghis Khan’s reform, promulgated at the 1206 kurultai, consecrated the victory of the new identity, that of members of the Mongol ulus, which was also of divine right and with similar universal imperial traits. Thereupon, the energies previously consumed in internal conflicts could be harnessed and channeled towards the outer world, where they produced epochal military victories. The analogy between these phenomena and those produced several centuries later by the French Revolution, which made possible, through a similar process of equalization, the “mass uprising” (levée en masse) and, as a consequence, Napoleon’s great conquests, is striking. -
Wave Nature of Matter: Made Easy (Lesson 3) Matter Behaving As a Wave? Ridiculous!
Wave Nature of Matter: Made Easy (Lesson 3) Matter behaving as a wave? Ridiculous! Compiled by Dr. SuchandraChatterjee Associate Professor Department of Chemistry Surendranath College Remember? I showed you earlier how Einstein (in 1905) showed that the photoelectric effect could be understood if light were thought of as a stream of particles (photons) with energy equal to hν. I got my Nobel prize for that. Louis de Broglie (in 1923) If light can behave both as a wave and a particle, I wonder if a particle can also behave as a wave? Louis de Broglie I’ll try messing around with some of Einstein’s formulae and see what I can come up with. I can imagine a photon of light. If it had a “mass” of mp, then its momentum would be given by p = mpc where c is the speed of light. Now Einstein has a lovely formula that he discovered linking mass with energy (E = mc2) and he also used Planck’s formula E = hf. What if I put them equal to each other? mc2 = hf mc2 = hf So for my photon 2 mp = hfhf/c/c So if p = mpc = hfhf/c/c p = mpc = hf/chf/c Now using the wave equation, c = fλ (f = c/λ) So mpc = hc /λc /λc= h/λ λ = hp So you’re saying that a particle of momentum p has a wavelength equal to Planck’s constant divided by p?! Yes! λ = h/p It will be known as the de Broglie wavelength of the particle Confirmation of de Broglie’s ideas De Broglie didn’t have to wait long for his idea to be shown to be correct. -
Samuel Goudsmit
NATIONAL ACADEMY OF SCIENCES SAMUEL ABRAHAM GOUDSMIT 1 9 0 2 — 1 9 7 8 A Biographical Memoir by BENJAMIN BEDERSON Any opinions expressed in this memoir are those of the author and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 2008 NATIONAL ACADEMY OF SCIENCES WASHINGTON, D.C. Photograph courtesy Brookhaven National Laboratory. SAMUEL ABRAHAM GOUDSMIT July 11, 1902–December 4, 1978 BY BENJAMIN BEDERSON AM GOUDSMIT LED A CAREER that touched many aspects of S20th-century physics and its impact on society. He started his professional life in Holland during the earliest days of quantum mechanics as a student of Paul Ehrenfest. In 1925 together with his fellow graduate student George Uhlenbeck he postulated that in addition to mass and charge the electron possessed a further intrinsic property, internal angular mo- mentum, that is, spin. This inspiration furnished the missing link that explained the existence of multiple spectroscopic lines in atomic spectra, resulting in the final triumph of the then struggling birth of quantum mechanics. In 1927 he and Uhlenbeck together moved to the United States where they continued their physics careers until death. In a rough way Goudsmit’s career can be divided into several separate parts: first in Holland, strictly as a theorist, where he achieved very early success, and then at the University of Michigan, where he worked in the thriving field of preci- sion spectroscopy, concerning himself with the influence of nuclear magnetism on atomic spectra. In 1944 he became the scientific leader of the Alsos Mission, whose aim was to determine the progress Germans had made in the development of nuclear weapons during World War II. -
Edward Mills Purcell (1912–1997)
ARTICLE-IN-A-BOX Edward Mills Purcell (1912–1997) Edward Purcell grew up in a small town in the state of Illinois, USA. The telephone equipment which his father worked with professionally was an early inspiration. His first degree was thus in electrical engineering, from Purdue University in 1933. But it was in this period that he realized his true calling – physics. After a year in Germany – almost mandatory then for a young American interested in physics! – he enrolled in Harvard for a physics degree. His thesis quickly led to working on the Harvard cyclotron, building a feedback system to keep the radio frequency tuned to the right value for maximum acceleration. The story of how the Manhattan project brought together many of the best physicists to build the atom bomb has been told many times. Not so well-known but equally fascinating is the story of radar, first in Britain and then in the US. The MIT radiation laboratory was charged with developing better and better radar for use against enemy aircraft, which meant going to shorter and shorter wavelengths and detecting progressively weaker signals. This seems to have been a crucial formative period in Purcell’s life. His coauthors on the magnetic resonance paper, Torrey and Pound, were both from this lab. I I Rabi, the physicist who won the 1944 Nobel Prize for measuring nuclear magnetic moments by resonance methods in molecular beams, was the head of the lab and a major influence on Purcell. Interestingly, Felix Bloch (see article on p.956 in this issue) was at the nearby Radio Research lab but it appears that the two did not interact much. -
11/03/11 110311 Pisp.Doc Physics in the Interest of Society 1
1 _11/03/11_ 110311 PISp.doc Physics in the Interest of Society Physics in the Interest of Society Richard L. Garwin IBM Fellow Emeritus IBM, Thomas J. Watson Research Center Yorktown Heights, NY 10598 www.fas.org/RLG/ www.garwin.us [email protected] Inaugural Lecture of the Series Physics in the Interest of Society Massachusetts Institute of Technology November 3, 2011 2 _11/03/11_ 110311 PISp.doc Physics in the Interest of Society In preparing for this lecture I was pleased to reflect on outstanding role models over the decades. But I felt like the centipede that had no difficulty in walking until it began to think which leg to put first. Some of these things are easier to do than they are to describe, much less to analyze. Moreover, a lecture in 2011 is totally different from one of 1990, for instance, because of the instant availability of the Web where you can check or supplement anything I say. It really comes down to the comment of one of Elizabeth Taylor later spouses-to-be, when asked whether he was looking forward to his wedding, and replied, “I know what to do, but can I make it interesting?” I’ll just say first that I think almost all Physics is in the interest of society, but I take the term here to mean advising and consulting, rather than university, national lab, or contractor research. I received my B.S. in physics from what is now Case Western Reserve University in Cleveland in 1947 and went to Chicago with my new wife for graduate study in Physics. -
I. I. Rabi Papers [Finding Aid]. Library of Congress. [PDF Rendered Tue Apr
I. I. Rabi Papers A Finding Aid to the Collection in the Library of Congress Manuscript Division, Library of Congress Washington, D.C. 1992 Revised 2010 March Contact information: http://hdl.loc.gov/loc.mss/mss.contact Additional search options available at: http://hdl.loc.gov/loc.mss/eadmss.ms998009 LC Online Catalog record: http://lccn.loc.gov/mm89076467 Prepared by Joseph Sullivan with the assistance of Kathleen A. Kelly and John R. Monagle Collection Summary Title: I. I. Rabi Papers Span Dates: 1899-1989 Bulk Dates: (bulk 1945-1968) ID No.: MSS76467 Creator: Rabi, I. I. (Isador Isaac), 1898- Extent: 41,500 items ; 105 cartons plus 1 oversize plus 4 classified ; 42 linear feet Language: Collection material in English Location: Manuscript Division, Library of Congress, Washington, D.C. Summary: Physicist and educator. The collection documents Rabi's research in physics, particularly in the fields of radar and nuclear energy, leading to the development of lasers, atomic clocks, and magnetic resonance imaging (MRI) and to his 1944 Nobel Prize in physics; his work as a consultant to the atomic bomb project at Los Alamos Scientific Laboratory and as an advisor on science policy to the United States government, the United Nations, and the North Atlantic Treaty Organization during and after World War II; and his studies, research, and professorships in physics chiefly at Columbia University and also at Massachusetts Institute of Technology. Selected Search Terms The following terms have been used to index the description of this collection in the Library's online catalog. They are grouped by name of person or organization, by subject or location, and by occupation and listed alphabetically therein. -
Alexandru Proca
ALEXANDRU PROCA (1897–1955) Dorin POENARU Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), Bucharest-Magurele, Romania and Frankfurt Institute for Advanced Studies (FIAS), J W Goethe University, Frankfurt am Main, Germany CLUSTER CD Dorin N. POENARU, IFIN-HH DECAYS A. Proca (1897–1955) – p.1/34 OUTLINE • Chronology • Impact on various branches of theoretical physics • Particles • Relativistic quantum fields • Klein-Gordon fields • Dirac field • Maxwell and Proca field • Hideki Yukawa and the Strong interaction • Einstein-Proca gravity. Dark matter, black holes. Tachyons. CLUSTER CD Dorin N. POENARU, IFIN-HH DECAYS A. Proca (1897–1955) – p.2/34 Chronology I • 1897 October 16: born in Bucharest • 1915 Graduate of the Gheorghe Lazar high school • 1917–18 Military School and 1st world war • 1918–22 student Polytechnical School (PS), Electromechanics • 1922–23 Engineer Electrical Society, Câmpina, and assistant professor of Electricity, PS Bucharest • 1923 Move to France: “I have something to say in Physics” • 1925 Graduate of Science Faculty, Sorbonne University, Paris CLUSTER CD Dorin N. POENARU, IFIN-HH DECAYS A. Proca (1897–1955) – p.3/34 Chronology II • 1925–27 researcher, Institut du Radium. Appreciated by Marie Curie • 1930–31 French citizen. L. de Broglie’s PhD student. Marie Berthe Manolesco became his wife • 1931–33 Boursier de Recherches, Institut Henri Poincaré • 1933 PhD thesis. Commission: Jean Perrin, L. Brillouin, L. de Broglie. Chargé de Recherches. After many years Proca will be Directeur de Recherches • 1934 One year with E. Schrödinger in Berlin and few months with N. Bohr in Copenhagen (met Heisenberg and Gamow) CLUSTER CD Dorin N. -
Quantum Theory Needs No 'Interpretation'
Quantum Theory Needs No ‘Interpretation’ But ‘Theoretical Formal-Conceptual Unity’ (Or: Escaping Adán Cabello’s “Map of Madness” With the Help of David Deutsch’s Explanations) Christian de Ronde∗ Philosophy Institute Dr. A. Korn, Buenos Aires University - CONICET Engineering Institute - National University Arturo Jauretche, Argentina Federal University of Santa Catarina, Brazil. Center Leo Apostel fot Interdisciplinary Studies, Brussels Free University, Belgium Abstract In the year 2000, in a paper titled Quantum Theory Needs No ‘Interpretation’, Chris Fuchs and Asher Peres presented a series of instrumentalist arguments against the role played by ‘interpretations’ in QM. Since then —quite regardless of the publication of this paper— the number of interpretations has experienced a continuous growth constituting what Adán Cabello has characterized as a “map of madness”. In this work, we discuss the reasons behind this dangerous fragmentation in understanding and provide new arguments against the need of interpretations in QM which —opposite to those of Fuchs and Peres— are derived from a representational realist understanding of theories —grounded in the writings of Einstein, Heisenberg and Pauli. Furthermore, we will argue that there are reasons to believe that the creation of ‘interpretations’ for the theory of quanta has functioned as a trap designed by anti-realists in order to imprison realists in a labyrinth with no exit. Taking as a standpoint the critical analysis by David Deutsch to the anti-realist understanding of physics, we attempt to address the references and roles played by ‘theory’ and ‘observation’. In this respect, we will argue that the key to escape the anti-realist trap of interpretation is to recognize that —as Einstein told Heisenberg almost one century ago— it is only the theory which can tell you what can be observed. -
1 WKB Wavefunctions for Simple Harmonics Masatsugu
WKB wavefunctions for simple harmonics Masatsugu Sei Suzuki Department of Physics, SUNY at Binmghamton (Date: November 19, 2011) _________________________________________________________________________ Gregor Wentzel (February 17, 1898, in Düsseldorf, Germany – August 12, 1978, in Ascona, Switzerland) was a German physicist known for development of quantum mechanics. Wentzel, Hendrik Kramers, and Léon Brillouin developed the Wentzel– Kramers–Brillouin approximation in 1926. In his early years, he contributed to X-ray spectroscopy, but then broadened out to make contributions to quantum mechanics, quantum electrodynamics, and meson theory. http://en.wikipedia.org/wiki/Gregor_Wentzel _________________________________________________________________________ Hendrik Anthony "Hans" Kramers (Rotterdam, February 2, 1894 – Oegstgeest, April 24, 1952) was a Dutch physicist. http://en.wikipedia.org/wiki/Hendrik_Anthony_Kramers _________________________________________________________________________ Léon Nicolas Brillouin (August 7, 1889 – October 4, 1969) was a French physicist. He made contributions to quantum mechanics, radio wave propagation in the atmosphere, solid state physics, and information theory. http://en.wikipedia.org/wiki/L%C3%A9on_Brillouin _______________________________________________________________________ 1. Determination of wave functions using the WKB Approximation 1 In order to determine the eave function of the simple harmonics, we use the connection formula of the WKB approximation. V x E III II I x b O a The potential energy is expressed by 1 V (x) m 2 x 2 . 2 0 The x-coordinates a and b (the classical turning points) are obtained as 2 2 a 2 , b 2 , m0 m0 from the equation 1 V (x) m 2 x2 , 2 0 or 1 1 m 2a 2 m 2b2 , 2 0 2 0 where is the constant total energy. Here we apply the connection formula (I, upward) at x = a. -
Black Holes and Qubits
Subnuclear Physics: Past, Present and Future Pontifical Academy of Sciences, Scripta Varia 119, Vatican City 2014 www.pas.va/content/dam/accademia/pdf/sv119/sv119-duff.pdf Black Holes and Qubits MICHAEL J. D UFF Blackett Labo ratory, Imperial C ollege London Abstract Quantum entanglement lies at the heart of quantum information theory, with applications to quantum computing, teleportation, cryptography and communication. In the apparently separate world of quantum gravity, the Hawking effect of radiating black holes has also occupied centre stage. Despite their apparent differences, it turns out that there is a correspondence between the two. Introduction Whenever two very different areas of theoretical physics are found to share the same mathematics, it frequently leads to new insights on both sides. Here we describe how knowledge of string theory and M-theory leads to new discoveries about Quantum Information Theory (QIT) and vice-versa (Duff 2007; Kallosh and Linde 2006; Levay 2006). Bekenstein-Hawking entropy Every object, such as a star, has a critical size determined by its mass, which is called the Schwarzschild radius. A black hole is any object smaller than this. Once something falls inside the Schwarzschild radius, it can never escape. This boundary in spacetime is called the event horizon. So the classical picture of a black hole is that of a compact object whose gravitational field is so strong that nothing, not even light, can escape. Yet in 1974 Stephen Hawking showed that quantum black holes are not entirely black but may radiate energy, due to quantum mechanical effects in curved spacetime. In that case, they must possess the thermodynamic quantity called entropy. -
Fantasy & Science Fiction V030n04
THE MA GAZINE Of Fantasy and JACK VANCE Science Fiction ISAAC ASIMOV J.T. MCINTOS NOVELETS We Can Remember It For You Wholesale Philip k. dick 4 The Sorcerer Pharesm JACK VANCE 79 SHORT STORIES Appoggiatura A. M, MARPLE 25 But Soft, What Light . CAROL EMSHWILLER 41 The Sudden Silence J. T. MCINTOSH 45 The Face Is Familiar GILBERT THOMAS 64 The Space Twins JAMES PULLEY 75 Bordered In Black LARRY NIVEN 112 FEATURES Cartoon GAHAN WILSON 24 Books JUDITH MERRIL 31 Injected Memory THEODORE L. THOMAS 62 Verse: The Octopus DORIS PITKIN BUCK 63 Science: The Nobelmen of Science ISAAC ASIMOV 101 F&SF Marketplace 129 Cover by Jack Gaughan (illustrating "The Sorcerer Pharesm”) Joseph W. Ferman, publishek Edward L. Ferman, editor Ted White, assistant editor Isaac Asimov, science editor Judith Merril, book editor Robert P. Mills, consulting editor Dale Beardale, aRCULATiON manager The Magazine of Fantasy and Science Fiction, Volume 30, No. 4, Whole No. 179, Apr. 1966. Published monthly by Mercury Press, Inc., at 504 o copy. Annual subscription $5.00; $5.50 in Canada and the Pan American Union, $6.00 in all other countries. Publication office, 10 Ferry Street, Concord, N. H. 03302. Editorial and general mail should be sent to 347 East 53rd St., New York, N. Y. 10022. Second Class postage paid at Concord, N. H. Printed in U.S.A. © 1966 by Mercury Press, Inc. All rights including translations into other languages, reserved. Submissions must be accompanied by stamped, self-addressed envelopes: the Publisher assumes no responsibility for return of unsolicited manuscripts. -
Otto Stern Annalen 4.11.11
(To be published by Annalen der Physik in December 2011) Otto Stern (1888-1969): The founding father of experimental atomic physics J. Peter Toennies,1 Horst Schmidt-Böcking,2 Bretislav Friedrich,3 Julian C.A. Lower2 1Max-Planck-Institut für Dynamik und Selbstorganisation Bunsenstrasse 10, 37073 Göttingen 2Institut für Kernphysik, Goethe Universität Frankfurt Max-von-Laue-Strasse 1, 60438 Frankfurt 3Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4-6, 14195 Berlin Keywords History of Science, Atomic Physics, Quantum Physics, Stern- Gerlach experiment, molecular beams, space quantization, magnetic dipole moments of nucleons, diffraction of matter waves, Nobel Prizes, University of Zurich, University of Frankfurt, University of Rostock, University of Hamburg, Carnegie Institute. We review the work and life of Otto Stern who developed the molecular beam technique and with its aid laid the foundations of experimental atomic physics. Among the key results of his research are: the experimental test of the Maxwell-Boltzmann distribution of molecular velocities (1920), experimental demonstration of space quantization of angular momentum (1922), diffraction of matter waves comprised of atoms and molecules by crystals (1931) and the determination of the magnetic dipole moments of the proton and deuteron (1933). 1 Introduction Short lists of the pioneers of quantum mechanics featured in textbooks and historical accounts alike typically include the names of Max Planck, Albert Einstein, Arnold Sommerfeld, Niels Bohr, Max von Laue, Werner Heisenberg, Erwin Schrödinger, Paul Dirac, Max Born, and Wolfgang Pauli on the theory side, and of Wilhelm Conrad Röntgen, Ernest Rutherford, Arthur Compton, and James Franck on the experimental side. However, the records in the Archive of the Nobel Foundation as well as scientific correspondence, oral-history accounts and scientometric evidence suggest that at least one more name should be added to the list: that of the “experimenting theorist” Otto Stern.