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Chapter 6 the Aftermath of the Cambridge-Vienna Controversy: Radioactivity and Politics in Vienna in the 1930S
Trafficking Materials and Maria Rentetzi Gendered Experimental Practices Chapter 6 The Aftermath of the Cambridge-Vienna Controversy: Radioactivity and Politics in Vienna in the 1930s Consequences of the Cambridge-Vienna episode ranged from the entrance of other 1 research centers into the field as the study of the atomic nucleus became a promising area of scientific investigation to the development of new experimental methods. As Jeff Hughes describes, three key groups turned to the study of atomic nucleus. Gerhard Hoffman and his student Heinz Pose studied artificial disintegration at the Physics Institute of the University of Halle using a polonium source sent by Meyer.1 In Paris, Maurice de Broglie turned his well-equipped laboratory for x-ray research into a center for radioactivity studies and Madame Curie started to accumulate polonium for research on artificial disintegration. The need to replace the scintillation counters with a more reliable technique also 2 led to the extensive use of the cloud chamber in Cambridge.2 Simultaneously, the development of electric counting methods for measuring alpha particles in Rutherford's laboratory secured quantitative investigations and prompted Stetter and Schmidt from the Vienna Institute to focus on the valve amplifier technique.3 Essential for the work in both the Cambridge and the Vienna laboratories was the use of polonium as a strong source of alpha particles for those methods as an alternative to the scintillation technique. Besides serving as a place for scientific production, the laboratory was definitely 3 also a space for work where tasks were labeled as skilled and unskilled and positions were divided to those paid monthly and those supported by grant money or by research fellowships. -
Global Austria Austria’S Place in Europe and the World
Global Austria Austria’s Place in Europe and the World Günter Bischof, Fritz Plasser (Eds.) Anton Pelinka, Alexander Smith, Guest Editors CONTEMPORARY AUSTRIAN STUDIES | Volume 20 innsbruck university press Copyright ©2011 by University of New Orleans Press, New Orleans, Louisiana, USA. All rights reserved under International and Pan-American Copyright Conventions. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without prior permission in writing from the publisher. All inquiries should be addressed to UNO Press, University of New Orleans, ED 210, 2000 Lakeshore Drive, New Orleans, LA, 70119, USA. www.unopress.org. Book design: Lindsay Maples Cover cartoon by Ironimus (1992) provided by the archives of Die Presse in Vienna and permission to publish granted by Gustav Peichl. Published in North America by Published in Europe by University of New Orleans Press Innsbruck University Press ISBN 978-1-60801-062-2 ISBN 978-3-9028112-0-2 Contemporary Austrian Studies Sponsored by the University of New Orleans and Universität Innsbruck Editors Günter Bischof, CenterAustria, University of New Orleans Fritz Plasser, Universität Innsbruck Production Editor Copy Editor Bill Lavender Lindsay Maples University of New Orleans University of New Orleans Executive Editors Klaus Frantz, Universität Innsbruck Susan Krantz, University of New Orleans Advisory Board Siegfried Beer Helmut Konrad Universität Graz Universität -
A New Look at Loschmidt's Representations of Benzene
Bull. Hist. Chem., VOLUME 38, Number 1 (2013) 29 150 YEARS AFTER THEIR EMERGENCE: A NEW LOOK AT LOSCHMIDT’S REPRESENTATIONS OF BENZENE Heinz D. Roth, Department of Chemistry and Chemical Biology, Wright-Rieman Laboratories, Rutgers University, New Brunswick, NJ 08854-8087, [email protected] Abstract to Kekulé’s theories, because, in the summary of Alan Rocke, they were “at once too empirical and too specula- A new examination of structures that Loschmidt tive” (10); von Meyer criticized Kekulé for not giving considered for benzene derivatives, notably naphthalene credit to Frankland for the concept of valence or to Kolbe and “rings” doubly bonded to O or triply bonded to N, or for his many contributions (11). show conclusively that Loschmidt did not view benzene More recent criticism has its roots in the work as a planar ring of six carbon atoms. of Kekulé’s biographer and successor on the Chair in Bonn, Richard Anschütz. While compiling material for Introduction his two-volume Kekulé biography (12), Anschütz found references to Couper (13), who had developed the idea August Kekulé has long been credited with several of linking carbon atoms independent of Kekulé; he also major contributions to structural organic chemistry: rec- noticed a footnote in Kekulé’s 1865 paper concerning ognizing the tetravalence of carbon (1857) (1,2); recog- structural formulae by Loschmidt. This 1861 article (14) nizing that carbon atoms combine with one another to had been published outside of the established chemical form chains (1858) (3); and recognizing the structure of literature and was not readily available. Anschütz noted benzene (1865) (4), in the view of Japp, the “crowning that Loschmidt’s booklet was hard to read (15); therefore, achievement of the doctrine of the linking of atoms” (5). -
Avogadro's Constant
Avogadro's Constant Nancy Eisenmenger Question Artem, 8th grade How \Avogadro constant" was invented and how scientists calculated it for the first time? Answer What is Avogadro's Constant? • Avogadros constant, NA: the number of particles in a mole • mole: The number of Carbon-12 atoms in 0.012 kg of Carbon-12 23 −1 • NA = 6:02214129(27) × 10 mol How was Avogadro's Constant Invented? Avogadro's constant was invented because scientists were learning about measuring matter and wanted a way to relate the microscopic to the macroscopic (e.g. how many particles (atoms, molecules, etc.) were in a sample of matter). The first scientists to see a need for Avogadro's constant were studying gases and how they behave under different temperatures and pressures. Amedeo Avogadro did not invent the constant, but he did state that all gases with the same volume, pressure, and temperature contained the same number of gas particles, which turned out to be very important to the development of our understanding of the principles of chemistry and physics. The constant was first calculated by Johann Josef Loschmidt, a German scientist, in 1865. He actually calculated the Loschmidt number, a constant that measures the same thing as Avogadro's number, but in different units (ideal gas particles per cubic meter at 0◦C and 1 atm). When converted to the same units, his number was off by about a factor of 10 from Avogadro's number. That may sound like a lot, but given the tools he had to work with for both theory and experiment and the magnitude of the number (∼ 1023), that is an impressively close estimate. -
Physiker-Entdeckungen Und Erdzeiten Hans Ulrich Stalder 31.1.2019
Physiker-Entdeckungen und Erdzeiten Hans Ulrich Stalder 31.1.2019 Haftungsausschluss / Disclaimer / Hyperlinks Für fehlerhafte Angaben und deren Folgen kann weder eine juristische Verantwortung noch irgendeine Haftung übernommen werden. Änderungen vorbehalten. Ich distanziere mich hiermit ausdrücklich von allen Inhalten aller verlinkten Seiten und mache mir diese Inhalte nicht zu eigen. Erdzeiten Erdzeit beginnt vor x-Millionen Jahren Quartär 2,588 Neogen 23,03 (erste Menschen vor zirka 4 Millionen Jahren) Paläogen 66 Kreide 145 (Dinosaurier) Jura 201,3 Trias 252,2 Perm 298,9 Karbon 358,9 Devon 419,2 Silur 443,4 Ordovizium 485,4 Kambrium 541 Ediacarium 635 Cryogenium 850 Tonium 1000 Stenium 1200 Ectasium 1400 Calymmium 1600 Statherium 1800 Orosirium 2050 Rhyacium 2300 Siderium 2500 Physiker Entdeckungen Jahr 0800 v. Chr.: Den Babyloniern sind Sonnenfinsterniszyklen mit der Sarosperiode (rund 18 Jahre) bekannt. Jahr 0580 v. Chr.: Die Erde wird nach einer Theorie von Anaximander als Kugel beschrieben. Jahr 0550 v. Chr.: Die Entdeckung von ganzzahligen Frequenzverhältnissen bei konsonanten Klängen (Pythagoras in der Schmiede) führt zur ersten überlieferten und zutreffenden quantitativen Beschreibung eines physikalischen Sachverhalts. © Hans Ulrich Stalder, Switzerland Jahr 0500 v. Chr.: Demokrit postuliert, dass die Natur aus Atomen zusammengesetzt sei. Jahr 0450 v. Chr.: Vier-Elemente-Lehre von Empedokles. Jahr 0300 v. Chr.: Euklid begründet anhand der Reflexion die geometrische Optik. Jahr 0265 v. Chr.: Zum ersten Mal wird die Theorie des Heliozentrischen Weltbildes mit geometrischen Berechnungen von Aristarchos von Samos belegt. Jahr 0250 v. Chr.: Archimedes entdeckt das Hebelgesetz und die statische Auftriebskraft in Flüssigkeiten, Archimedisches Prinzip. Jahr 0240 v. Chr.: Eratosthenes bestimmt den Erdumfang mit einer Gradmessung zwischen Alexandria und Syene. -
'How?' Arxiv:2107.02558V1 [Physics.Hist-Ph] 6 Jul 2021
Understanding Physics: ‘What?’, ‘Why?’, and ‘How?’ Mario Hubert California Institute of Technology Division of the Humanities and Social Sciences —— Forthcoming in the European Journal for Philosophy of Science July 7, 2021 I want to combine two hitherto largely independent research projects, scientific un- derstanding and mechanistic explanations. Understanding is not only achieved by answering why-questions, that is, by providing scientific explanations, but also by answering what-questions, that is, by providing what I call scientific descriptions. Based on this distinction, I develop three forms of understanding: understanding-what, understanding-why, and understanding-how. I argue that understanding-how is a par- ticularly deep form of understanding, because it is based on mechanistic explanations, which answer why something happens in virtue of what it is made of. I apply the three forms of understanding to two case studies: first, to the historical development of ther- modynamics and, second, to the differences between the Clausius and the Boltzmann entropy in explaining thermodynamic processes. arXiv:2107.02558v1 [physics.hist-ph] 6 Jul 2021 i Contents 1 Introduction 1 2 Scientific Inquiry as Asking ‘Why?’ and ‘What?’ 3 2.1 The Origin and Epistemic Goals of Scientific Inquiry . 3 2.2 Scientific Descriptions and Aristotle’s Four Causes . 6 3 Scientific Descriptions and Mechanisms 10 4 A Critique of Current Theories of Understanding 11 4.1 Grimm’s Account . 12 4.2 De Regt’s Contextual Theory of Understanding . 14 5 Thermodynamics and Statistical Mechanics 17 5.1 Understanding in the Historical Development . 18 5.2 Entropy: Clausius and Boltzmann . 24 5.2.1 Clausius Entropy . -
In Praise of Clausius Entropy 01/26/2021
In Praise of Clausius Entropy 01/26/2021 In Praise of Clausius Entropy: Reassessing the Foundations of Boltzmannian Statistical Mechanics Forthcoming in Foundations of Physics Christopher Gregory Weaver* Assistant Professor of Philosophy, Department of Philosophya Affiliate Assistant Professor of Physics, Department of Physicsb Core Faculty in the Illinois Center for Advanced Studies of the Universeb University of Illinois at Urbana-Champaign Visiting Fellow, Center for Philosophy of ScienceC University of Pittsburgh *wgceave9@illinois [dot] edu (or) CGW18@pitt [dot] edu aDepartment of Philosophy 200 Gregory Hall 810 South Wright ST MC-468 Urbana, IL 61801 bDepartment of Physics 1110 West Green ST Urbana, IL 61801 CCenter for Philosophy of Science University of Pittsburgh 1117 Cathedral of Learning 4200 Fifth Ave. Pittsburgh, PA 15260 1 In Praise of Clausius Entropy 01/26/2021 Acknowledgments: I thank Olivier Darrigol and Matthew Stanley for their comments on an earlier draft of this paper. I thank Jochen Bojanowski for a little translation help. I presented a version of the paper at the NY/NJ (Metro Area) Philosophy of Science group meeting at NYU in November of 2019. I’d like to especially thank Barry Loewer, Tim Maudlin, and David Albert for their criticisms at that event. Let me extend special thanks to Tim Maudlin for some helpful correspondence on various issues addressed in this paper. While Professor Maudlin and I still disagree, that correspondence was helpful. I also presented an earlier draft of this work to the Department of Physics at the University of Illinois at Urbana-Champaign in January 2020. I thank many of the physics faculty and graduate students for their questions and objections. -
Measurements and Uncertainty
Measurements and Uncertainty Measurement = comparing a value with a unit Measurement = read between the scale division marks, estimate the measurement to the nearest one tenth of the space between scale divisions Significant Figures = digits read from the scale + the last estimated digit Measurement error = minimum ±1 of the last digit 1 Measurement 32.33 °C What is the 32.3 °C smallest scale division 2 Reading from a digital display error = ±1 of the last digit 3 Accuracy and Precision Every measurement has its error Repeated measurements - error estimation Precision = is the degree to which repeated measurements show the same results, depends on the abilities of experimentator Accuracy = the agreement between experimental data and a known value, depends on instrument quality 4 Weighing 5 Number of significant figures is given by the instrument quality Significant Figures • All nonzero digits are significant 3.548 • Zeroes between nonzero digits are significant 3.0005 • Leading zeros to the left of the first nonzero digits are not significant 0.0034 • Trailing zeroes that are also to the right of a decimal point in a number are significant 0.003400 • When a number ends in zeroes that are not to the right of a decimal point, the zeroes are not necessarily significant 1200 Ambiguity avoided by the use of standard exponential, or "scientific," notation: 1.2 103 or 1.200 103 depending on the number of significant figures 6 Significant Figures Reading from a scale – number of significant figures is given by the instrument quality 8.75 cm3 -
Entropy and Energy, – a Universal Competition
Entropy 2008, 10, 462-476; DOI: 10.3390/entropy-e10040462 OPEN ACCESS entropy ISSN 1099-4300 www.mdpi.com/journal/entropy Article Entropy and Energy, – a Universal Competition Ingo Müller Technical University Berlin, Berlin, Germany E-mail: [email protected] Received: 31 July 2008; in revised form: 9 September 2008 / Accepted: 22 September 2008 / Published: 15 October 2008 Abstract: When a body approaches equilibrium, energy tends to a minimum and entropy tends to a maximum. Often, or usually, the two tendencies favour different configurations of the body. Thus energy is deterministic in the sense that it favours fixed positions for the atoms, while entropy randomizes the positions. Both may exert considerable forces in the attempt to reach their objectives. Therefore they have to compromise; indeed, under most circumstances it is the available free energy which achieves a minimum. For low temperatures that free energy is energy itself, while for high temperatures it is determined by entropy. Several examples are provided for the roles of energy and entropy as competitors: – Planetary atmospheres; – osmosis; – phase transitions in gases and liquids and in shape memory alloys, and – chemical reactions, viz. the Haber Bosch synthesis of ammonia and photosynthesis. Some historical remarks are strewn through the text to make the reader appreciate the difficulties encountered by the pioneers in understanding the subtlety of the concept of entropy, and in convincing others of the validity and relevance of their arguments. Keywords: concept of entropy, entropy and energy 1. First and second laws of thermodynamics The mid-nineteenth century saw the discovery of the two laws of thermodynamics, virtually simultaneously. -
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. -
Maxwell's Demon and the Second Law of Thermodynamics
GENERAL ARTICLE Maxwell’s Demon and the Second Law of Thermodynamics P Radhakrishnamurty A century and a half ago, Maxwell introduced a thought experiment to illustrate the difficulties which arise in trying to apply the second law of thermodynamics at the level of molecules. He imagined an entity (since personified as ‘Mawell’s demon’) which could sort molecules into hot and Dr Radhakrishnamurthy cold and thereby create differences of temperature spontane- obtained his PhD from the ously, apparently violating the second law. This topic has Indian Institute of Science, Bangalore, after which he fascinated physicists and has generated much discussion and worked as a scientist at the many new ideas, which this article goes over. Particularly Central Electrochemical interesting is the insight given by deeper analysis of the Research Institute, experiment. This brings out the relation between entropy and Karaikudi. He is now retired and enjoys reading information, and the role of irreversibility in computing as we and writing on topics in understand it – topics still under discussion today. science. His present research interests include Introduction classical thermodynamics and elastic collision theory. The science of thermodynamics is nearly 200 years old. It took birth in the works of Carnot around the year 1824 and grew into 1 It does not say anything about a subject of great significance. Just four simple laws – the zeroth the process being possible in practice. The distinction is ex- law, the first law, the second law and the third law – govern emplified by the simple example: thermodynamics. The first and the second laws are the bones and Theromodynamics says the the flesh of thermodynamics, and by comparison the zeroth and combination of hydrogen and the third laws are mere hat and slippers, in the language of Shee- oxygen to give water under con- ditions of room termperature and han. -
CONTEMPORARY AUSTRIAN STUDIES | Volume 20
Global Austria Austria’s Place in Europe and the World Günter Bischof, Fritz Plasser (Eds.) Anton Pelinka, Alexander Smith, Guest Editors CONTEMPORARY AUSTRIAN STUDIES | Volume 20 innsbruck university press Copyright ©2011 by University of New Orleans Press, New Orleans, Louisiana, USA. All rights reserved under International and Pan-American Copyright Conventions. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without prior permission in writing from the publisher. All inquiries should be addressed to UNO Press, University of New Orleans, ED 210, 2000 Lakeshore Drive, New Orleans, LA, 70119, USA. www.unopress.org. Book design: Lindsay Maples Cover cartoon by Ironimus (1992) provided by the archives of Die Presse in Vienna and permission to publish granted by Gustav Peichl. Published in North America by Published in Europe by University of New Orleans Press Innsbruck University Press ISBN 978-1-60801-062-2 ISBN 978-3-9028112-0-2 Contemporary Austrian Studies Sponsored by the University of New Orleans and Universität Innsbruck Editors Günter Bischof, CenterAustria, University of New Orleans Fritz Plasser, Universität Innsbruck Production Editor Copy Editor Bill Lavender Lindsay Maples University of New Orleans University of New Orleans Executive Editors Klaus Frantz, Universität Innsbruck Susan Krantz, University of New Orleans Advisory Board Siegfried Beer Helmut Konrad Universität Graz Universität