Placing Chandra's Work in Historical Context
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On the Concept of Degenerate Stars: the Case of White Dwarfs
On the concept of degenerate stars: the case of white dwarfs Michael Rotondo - Istituto di Istruzione Superiore Statale “Pacinotti-Archimede”, Roma - [email protected] Abstract: In this work we briefly review the history of degenerate stars from the first introduction of Fermi-Dirac quantum statistics to the first unified approach of white dwarfs, based on the relativistic generalization of the Feynman-Metropolis-Teller of compressed atoms, which takes into account consistently the gravitational, the weak, the strong and the electromagnetic interactions. Keywords:History of astrophysics, Compact stars, Degenerate Fermi gas 1. Prologue: Adams and Eddington Exactly one century ago Walter S. Adams published a paper entitled “The Spectrum of the Companion of Sirius” in which he concludes that: …the companion of Sirius has a color index not appreciably different from that of the principal star (Adams 1915, p. 237). This conclusion would lead to a dramatic consequence as summarized by Arthur S. Ed- dington: …a ton of [companion of Sirius] material would be a little nugget that you could put in a match-box. What reply can one make to such a message? The reply which most of us made in 1914 was - ‘Shut up. Don’t talk nonsense’ (Eddington 1927, p. 50). Nine years later, in 1924, Eddington published a paper entitled “On the Relation be- tween the Masses and Luminosities of the Stars” in which he suggested a new test to confirm (or reject) the exceptionally high density of the companion of Sirius: …the question could probably be settled by measuring Einstein shift of the spec- trum… (Eddington 1924, p. -
Philosophy and the Physicists Preview
L. Susan Stebbing Philosophy and the Physicists Preview il glifo ebooks ISBN: 9788897527466 First Edition: December 2018 (A) Copyright © il glifo, December 2018 www.ilglifo.it 1 Contents FOREWORD FROM THE EDITOR Note to the 2018 electronic edition PHILOSOPHY AND THE PHYSICISTS Original Title Page PREFACE NOTE PART I - THE ALARMING ASTRONOMERS Chapter I - The Common Reader and the Popularizing Scientist Chapter II - THE ESCAPE OF SIR JAMES JEANS PART II - THE PHYSICIST AND THE WORLD Chapter III - ‘FURNITURE OF THE EARTH’ Chapter IV - ‘THE SYMBOLIC WORLD OF PHYSICS’ Chapter V - THE DESCENT TO THE INSCRUTABLE Chapter VI - CONSEQUENCES OF SCRUTINIZING THE INSCRUTABLE PART III - CAUSALITY AND HUMAN FREEDOM Chapter VII - THE NINETEENTH-CENTURY NIGHTMARE Chapter VIII - THE REJECTION OF PHYSICAL DETERMINISM Chapter IX - REACTIONS AND CONSEQUENCES Chapter X - HUMAN FREEDOM AND RESPONSIBILITY PART IV - THE CHANGED OUTLOOK Chapter XI - ENTROPY AND BECOMING Chapter XII - INTERPRETATIONS BIBLIOGRAPHY INDEX BACK COVER Susan Stebbing 2 Foreword from the Editor In 1937 Susan Stebbing published Philosophy and the Physicists , an intense and difficult essay, in reaction to reading the works written for the general public by two physicists then at the center of attention in England and the world, James Jeans (1877-1946) and Arthur Eddington (1882- 1944). The latter, as is known, in 1919 had announced to the Royal Society the astronomical observations that were then considered experimental confirmations of the general relativity of Einstein, and who by that episode had managed to trigger the transformation of general relativity into a component of the mass and non-mass imaginary of the twentieth century. -
The 29 of May Or Sir Arthur and The
International Journal of Management and Applied Science, ISSN: 2394-7926 Volume-4, Issue-4, Apr.-2018 http://iraj.in THE 29TH OF MAY OR SIR ARTHUR AND THE BENDING LIGHT (TEACHING SCIENCE AND LITERATURE JOINTLY) MICHAEL KATZ Faculty of Education, Haifa University, Mount Carmel, Haifa, Israel E-mail: [email protected] Abstract - In this paper I present an instance illustrating a program of joint teaching of science and literature. The instance sketched here rests on recognition that at the age when children read books like Kästner's "The 35th of May" they can already taste notions of Relativity Theory through the story of Eddington's expedition to Principe Island. Eddington's story is briefly recounted here with references to Kästner's book. The relationships thus exhibited between science and fiction, fantasy and reality, theory and actuality, humor and earnestness, should help evoke school age children's interest in science and literature at early stages in their studies' endeavor. Keywords - Bending Light, Fantasy, Gravitation, Relativity, Science and Literature. I. INTRODUCTION South Seas" – a story of adventure and humor by Erich Kästner, the well known German author of The idea that teaching science and humanities in more than a few dearly loved novels, mostly for primary and secondary schools needn't necessarily be children and adolescents. The book was first seen as disjoint objectives is prevalent in the thought published in German in 1931 and in English shortly and practice of more than a few scholars and teachers after. in recent years. Carole Cox [1], for example, unfolds forty strategies of literature based teaching of various Twelve years earlier, in 1919, another journey topics in arts and sciences. -
Revised Theory of Gravity Doesn't Predict a Big Bang 12 July 2010, by Lisa Zyga
Revised theory of gravity doesn't predict a Big Bang 12 July 2010, By Lisa Zyga decades he became more interested in finding a theory to unify gravity and quantum mechanics - a task that is still being studied today. In 1924, Eddington proposed a new “gravitational action” as an alternative to the Einstein-Hilbert action, which could serve as an alternative starting point to general relativity. In astrophysics, a gravitational action is the mechanism that describes how gravity can emerge from space-time being curved by matter and energy. However, Eddington’s theory of gravity only worked for empty space and didn’t Illustration: Time Line of the Universe Credit: include any source of energy such as matter, NASA/WMAP making it an incomplete theory. Since Eddington’s proposal, scientists have attempted various ways of including matter into the (PhysOrg.com) -- The Big Bang theory has formed theory, although they have run into problems. In the basis of our understanding of the universe's this study, Banados and Ferreira have tried a new origins since it was first proposed in 1927 by way to extend the theory to include matter by using Georges Lemaitre. And for good reason: the theory a gravitational action called the Born-Infeld action. is supported by scientists' latest observations and experiments, and is based on Einstein's widely In their analysis, the scientists found that a key accepted theory of general relativity. But scientists characteristic of Eddington’s revised theory of are always on the lookout for any evidence that gravity is that it reproduces Einstein gravity might suggest an alternative to the Big Bang. -
Eddington, Lemaître and the Hypothesis of Cosmic Expansion in 1927
Eddington, Lemaître and the hypothesis of cosmic expansion in 1927 Cormac O’Raifeartaigh School of Science and Computing, Waterford Institute of Technology, Cork Road, Waterford, Ireland Author for correspondence: [email protected] 1 1. Introduction Arthur Stanley Eddington was one of the leading astronomers and theorists of his generation (Smart et al. 1945; McCrea 1982; Chandrasekhar, S. 1983). An early and important proponent of the general theory of relativity, his 1918 ‘Report on the Relativity Theory of Gravitation’ for the Physical Society (Eddington 1918) provided an early authoritative exposition of the subject for English-speaking physicists (Vibert Douglas 1956 p42; Chandrasekhar 1983 p24). He played a leading role in the eclipse observations of 1919 that offered early astronomical evidence in support of the theory (Vibert Douglas 1956 pp 39-41; Chandrasekhar 1983 pp 24- 29; Kennefick, this volume) while his book ‘Space, Time and Gravitation’ (Eddington 1920) was one of the first popular treatises on general relativity for an English-speaking audience. In addition, Eddington’s textbook ‘The Mathematical Theory of Relativity’ (Eddington 1923) became a classic reference for English-speaking physicists with an interest in relativity (McCrea 1982; Chandrasekhar 1983 p32). Indeed, the book provided one of the first textbook accounts of relativistic models of the cosmos, complete with a discussion of possible links to one of the greatest astronomical puzzles of the age, the redshifts of the spiral nebulae (Eddington 1923 pp 155-170). It seems therefore quite surprising that, when Eddington’s former student Georges Lemaître suggested in a seminal article of 1927 (Lemaître 1927) that a universe of expanding radius could be derived from general relativity, and that the phenomenon could provide a natural explanation for the redshifts of the spiral nebulae, Eddington (and others) paid no attention. -
90 Years on – the 1919 Eclipse Expedition at Príncipe
ELLIS ET AL.: 1919 ECLIPSE REVISITED ELLIS ET AL.: 1919 ECLIPSE REVISITED 90 years on – the 1919 ecli pse expedition at Príncipe Richard Ellis, Pedro G Ferreira, Richard Massey and Gisa Weszkalnys return to Príncipe in the International Year of Astronomy to celebrate the 1919 RAS expedition led by Sir Arthur Eddington. he first experiment to observationally stars near the Sun are confirm Einstein’s General Theory of not normally visible, TRelativity was carried out in May 1919, they would be during on a Royal Astronomical Society expedition to a total solar eclipse. observe a total solar eclipse. Sir Arthur Edding- Einstein attempted ton travelled to Príncipe, a small island off the to convince observers west coast of Africa, and sent another team to to measure the gravi- Sobral, Brazil, from where the eclipse would tational deflection. He also be visible. This year, in a new RAS-funded found an enthusiastic expedition organized for the International Year colleague in Erwin of Astronomy, we returned to Príncipe to cel- Findlay-Freundlich, 1: The old plantation buildings at Roça Sundy, Eddington’s base in 1919. ebrate this key experiment that shook the foun- whose expedition to dations of 20th-century science. Russia in August 1914 was scuppered by the America and Africa, but it was important to Since 1687, Sir Isaac Newton’s law of gravity outbreak of war in the very month of the solar be as close as possible to the sub-solar point, had been the workhorse of celestial mechanics. eclipse: as a German national in Russia, he where the Earth’s rotation keeps observers in Newtonian gravity could be used to explain the was arrested. -
The Eclipse to Confirm the General Theory of Relativity - Openmind Search Private Area
8/9/2015 The Eclipse to Confirm the General Theory of Relativity - OpenMind Search Private area Sharing knowledge for a better future Home The Eclipse to Confirm the General Theory of Relativity The Eclipse to Confirm the General Theory of Relativity Share 20 July 2015 Physics, Science 1 Sign in or register to rate this publication One of the milestones of the science of light commemorated during this International Year of Light and Light-based Technologies is “the embedding of light in cosmology through general relativity in 1915,” that is, the celebration of the centenary of Albert Einstein’s general theory of relativity. As Adolfo de Azcárraga, president of the Spanish Royal Society of Physics (RSEF), points out in his book titled Albert Einstein, His Science and His Time, Einstein’s theory contained a spectacular prediction: “light also possessed ‘weight’, i.e., it should be attracted and deflected by celestial bodies.” Since the equivalence between acceleration and gravity extends to electromagnetic phenomena and light is an electromagnetic wave, light rays should bend in the presence of a gravitational field. Einstein had already realized that the only way to experimentally verify this theoretical prediction was for a total solar eclipse to take place since this would make it possible to photograph a star near the Sun when observed from Earth without the presence of strong sunlight. Well, on May 29, 1919 there would be a solar eclipse, which would be total on some parts of the Earth’s surface and would make it possible to verify that light rays are bent by gravity. -
Subrahmanyan Chandrasekhar – Geniaalne Astrofüüsik
Subrahmanyan Chandrasekhar – geniaalne astrofüüsik Sissejuhatus Kuulsin Chandrasekhari nime esimest korda, kui mu sõber ja hilisem kolleeg Tiit Nilson oli saanud veel ülikooliajal – 1962. aastal - oma juhendajaks Juhan Rossi. Tiit näitas mulle Juhani käest saadud vene keelde tõlgitud Chandrasekhari raamatut kiirguslevist, mis oli täis salapäraseid valemeid. Hiljem sai see raamat mullegi väga oluliseks ja 1977. a ostsin selle – inglisekeelsena – Lõuna-California ülikooli raamatupoest Los Angeleses. Sellest ajast on see mu töölauaraamat, ja minuni jõudis arusaamine sellest, et see mees on haruldaselt mitmekülgne suur teadlane. Mingi tõsise probleemi ettevõtnuna avaldas ta terve seeria artikleid probleemi lahenduse kohta ja siis järgnes artikleid kokkuvõttev monograafia. Nii said põhjaliku ülevaate ja lahenduse tähe siseehitus, sh valgete kääbuste ehitus, stellaardünaamika, stohhastilised protsessid, kiirguslevi, negatiivse vesiniku iooni kvantteooria, hüdrodünaamika ja hüdromagnetiline stabiilsus, turbulents, tasakaaluliste objektide tasakaal, üldine relatiivsusteooria, mustade aukude matemaatiline teooria ja põrkuvate gravitatsioonilainete teooria. Lisaks veel Newtoni kuulsa Principia „tõlkimine“ autori geomeetrilisest keelest tänapäevasesse keelde. Mida rohkemat veel ühelt inimeselt nõuda võiks! Lapsepõlv ja perekond Chandrasekhar sündis tolleaegses Briti India (nüüd Pakistani) Punjabi provintsi linnas Lahores 19. oktoobril 1910 Chandrasekhara Subrahmanyan Ayyari (1885-1960) ja tema abikaasa Sitalakshmi (1891-1931) esimese pojana. Kokku -
One of the Most Celebrated Physics Experiments of the 20Th Cent
Not Only Because of Theory: Dyson, Eddington and the Competing Myths of the 1919 Eclipse Expedition Introduction One of the most celebrated physics experiments of the 20th century, a century of many great breakthroughs in physics, took place on May 29th, 1919 in two remote equatorial locations. One was the town of Sobral in northern Brazil, the other the island of Principe off the west coast of Africa. The experiment in question concerned the problem of whether light rays are deflected by gravitational forces, and took the form of astrometric observations of the positions of stars near the Sun during a total solar eclipse. The expedition to observe the eclipse proved to be one of those infrequent, but recurring, moments when astronomical observations have overthrown the foundations of physics. In this case it helped replace Newton’s Law of Gravity with Einstein’s theory of General Relativity as the generally accepted fundamental theory of gravity. It also became, almost immediately, one of those uncommon occasions when a scientific endeavor captures and holds the attention of the public throughout the world. In recent decades, however, questions have been raised about possible bias and poor judgment in the analysis of the data taken on that famous day. It has been alleged that the best known astronomer involved in the expedition, Arthur Stanley Eddington, was so sure beforehand that the results would vindicate Einstein’s theory that, for unjustifiable reasons, he threw out some of the data which did not agree with his preconceptions. This story, that there was something scientifically fishy about one of the most famous examples of an experimentum crucis in the history of science, has now become well known, both amongst scientists and laypeople interested in science. -
+ Gravity Probe B
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION Gravity Probe B Experiment “Testing Einstein’s Universe” Press Kit April 2004 2- Media Contacts Donald Savage Policy/Program Management 202/358-1547 Headquarters [email protected] Washington, D.C. Steve Roy Program Management/Science 256/544-6535 Marshall Space Flight Center steve.roy @msfc.nasa.gov Huntsville, AL Bob Kahn Science/Technology & Mission 650/723-2540 Stanford University Operations [email protected] Stanford, CA Tom Langenstein Science/Technology & Mission 650/725-4108 Stanford University Operations [email protected] Stanford, CA Buddy Nelson Space Vehicle & Payload 510/797-0349 Lockheed Martin [email protected] Palo Alto, CA George Diller Launch Operations 321/867-2468 Kennedy Space Center [email protected] Cape Canaveral, FL Contents GENERAL RELEASE & MEDIA SERVICES INFORMATION .............................5 GRAVITY PROBE B IN A NUTSHELL ................................................................9 GENERAL RELATIVITY — A BRIEF INTRODUCTION ....................................17 THE GP-B EXPERIMENT ..................................................................................27 THE SPACE VEHICLE.......................................................................................31 THE MISSION.....................................................................................................39 THE AMAZING TECHNOLOGY OF GP-B.........................................................49 SEVEN NEAR ZEROES.....................................................................................58 -
Chandrasekhar and the History of Astronomy
Chandrasekhar and the history of astronomy Virginia Trimble· Department of Physics and Astronomy, Universiry of California, Irvine CA 92697, USA, and Las Cumbres Observatory Global Telescope Network. Goleta, California, USA Received August 12, 2011 Abstract. Chandrasekhar's own books, papers, and oral history interviews make clear that he was generally more interested in the present and future of astrophysics than in its past. Nevertheless, late in his life and after his death, historians of science have somewhat entangled him in two supposedly contro versial issues, one concerning precursors of his mass limit for degenerate stars and the other his relationship with Eddington. Neither story is an entirely happy one. 1. The fate of famous scientists Biographers write biographies and historians write books and papers, and no one, living or dead, has much defense against them. Among scientists I've known, Richard Feynman, Fred Hoyle, and Carl Sagan have each been the subject of at least three. Thus no one should be surprised that there are biographies and encyclopedia articles about Chandra (Wali 1991 , 2008) and Eddington (Douglas 1956; Stanley 2007, 2008), and indeed even a biography of Eddington by Chandrasekhar ( 1983). Not that you had any doubts before, but you cannot come away from any of these without realizing that each made both extraordinarily many and extraordinarily important contributions to 20th century astrophysics. But be thou chaste as ice, as pure as snow, thou shalt not escape calumny (Hamlet, Act ill, Sc. l, to save you looking it up). 2. Degenerate stars, or, who discovered the Chandrasekhar limit? I first encountered this issue more than 30 years ago (Trimble 1979) when I reviewed a semi-popular book by l.S. -
Review of L. S. Stebbing, Philosophy and the Physicists
NEW BOOKS Philosophy and the Physicists. By L. S. STEBBING.(London: Methuen & Co. 1937. Pp. xvi + 295. Price 7s. 6d.) Professor Stebbing's book is intended to assess the philosophical value, if any, of the numerous works in which certain eminent scientists have ex- pounded to the general public what they consider to be the implications of recent developments in mathematical physics. The writers whom she mainly discusses are Sir James Jeans and Sir Arthur Eddington. She complains, with some justice, that they both "approach their task through an emotional, fog," and both "present their views with an amount of personification and metaphor that reduces them to the level of revivalist preachers." This is a severe judgment, but it appears to me to be amply borne out by my own experience in reading their works, and by the quotations which Miss Stebbing gives. I find myself in complete agreement with her remark on p. I8, that "the fundamental objection to the modes of expression so dear to Eddington and Jeans . is that such writing obfuscates the common reader whilst pretending to enlighten him." The two writers under discussion are, as Miss Stebbing recognizes, of very different calibre when considered as contributors to philosophy. There is no evidence that Jeans has any serious contribution to make, and Miss Stebbing disposes of his puerilities in a couple of chapters. This massacre is too much like knocking down a sitting bird to be of much interest, and Miss Stebbing devotes the rest of her book to the more sportsmanlike exercise of peppering Eddington as he flits from one metaphor to another.