Transmitting Knowledge across Divides

One model, the resonance model, shaped scientific understanding of optical dispersion from the early 1870s to the 1920s, persisting across dramatic changes in physical conceptions of light and matter. I explore the ways in which the model was transmitted across these conceptual divides by analyzing the use of the model both in the development of theories of optical dispersion and in the interpretation of experimental data. Crucial to this analysis is the integration of the model into quantum theory because of the conceptual incompatibility between the model and quantum theory. What is more, a quantum understanding of optical dispersion set the grounds for the emergence of the first theories of quantum mechanics in 1925. A long-term history of the model’s transmission from the 1870s to the 1920s illuminates the ways in which the continuity of knowledge is possible across these discontinuities.

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Introduction

10.1093/oso/9780190652913.003.0001 ◽

2017 ◽

Author(s):

Henk W. de Regt

Keyword(s):

Quantum Mechanics ◽

History Of Science ◽

Crucial Role ◽

Scientific Understanding ◽

Failures

Constructing Quantum Mechanics ◽

10.1093/oso/9780198845478.003.0007 ◽

2019 ◽

pp. 300-382

Author(s):

Anthony Duncan ◽

Michel Janssen

Keyword(s):

Quantum Mechanics ◽

Quantum Theory ◽

Ground State Energy ◽

Ground State ◽

Equations Of Motion ◽

Zeeman Effect ◽

Stationary States ◽

Old Quantum Theory ◽

History Of ◽

Anomalous Zeeman Effect

We consider three topics which proved frustratingly resistant to the methods of the old quantum theory up to the point of emergence of the quantum mechanics of Heisenberg and collaborators in late 1925. First, the old theory could not account convincingly for the superfluity of stationary states implied by the existence of the complex multiplets seen in most atomic spectra. Second, the progressively more complicated theories proposed for explaining the splittings of lines in the anomalous Zeeman effect were found to lead inevitably to glaring inconsistencies with the assumed mechanical equations of motion. Finally, there was the problem of the dual spectrum of helium, and even more basically, of the ground state energy of helium, all calculations of which in terms of specified electron orbits gave incorrect results. We relate the tangled history of the efforts to provide a theoretical resolution of these problems within the old quantum theory.

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Jagdish Mehra & Helmut Rechenberg. The Historical Development of Quantum Theory. Volume 1, The Quantum Theory of Planck, Einstein, Bohr and Sommerfeld: Its Foundations and the Rise of its Difficulties 1900–1925. Volume 2, The Discovery of the Quantum Mechanics 1925. Volume 3, The Formulation of Matrix Mechanics and its Modifications 1925–1926. Volume 4, The Fundamental Equations of Quantum Mechanics 1925–1926 and The Reception of the New Quantum Mechanics 1925–1926. New York, Heidelberg and Berlin: Springer-Verlag, 1982. Volume 1 in two parts, pp. xlvii + 372, vi + 506. ISBN 3-540-90642-8, 3-540-90667-3. DM 75, DM 85. Volume 2, pp. vii + 355. ISBN 3-540-90674-6. DM 65. Volume 3, pp. vii + 334. ISBN 3-540-90675-4. DM 75. Volume 4, pp. viii + 322. ISBN 3-540-90680-0. DM 75. - Andrew Pickering. Constructing Quarks. A Sociological History of Particle Physics. Edinburgh: Edinburgh University Press, 1984. Pp. xi + 468. ISBN 0-85224-458-4 £20.

The British Journal for the History of Science ◽

10.1017/s0007087400023001 ◽

1986 ◽

Vol 19 (2) ◽

pp. 206-208

Author(s):

John Hendry

Keyword(s):

New York ◽

Quantum Mechanics ◽

Quantum Theory ◽

Particle Physics ◽

Historical Development ◽

Matrix Mechanics ◽

History Of Particle Physics ◽

History Of ◽

Sociological History ◽

Fundamental Equations

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Atypical Femoral Fracture in McCune-Albright Syndrome

Journal of Research in Orthopedic Science ◽

10.32598/jrosj.7.3.711.1 ◽

2020 ◽

Vol 7 (3) ◽

pp. 147-152

Author(s):

Salman Ghaffari ◽

◽

Mehran Razavipour ◽

Parastoo Mohammad Amini ◽

◽

...

Keyword(s):

Femoral Fracture ◽

Dynamic Compression ◽

Plate Fixation ◽

Medullary Canal ◽

Mccune Albright Syndrome ◽

Café Au Lait Spots ◽

History Of ◽

Albright Syndrome ◽

Mccune Albright

McCune-Albright Syndrome (MAS) is characterized by endocrinopathies, café-au-lait spots, and fibrous dysplasia. Bisphosphonates are the most prescribed treatment for reducing the pain but their long-term use has been associated with atypical fractures of cortical bones like femur in patients. We present a 23-year-old girl diagnosed with MAS. She had an atypical mid-shaft left femoral fracture that happened during simple walking. She also had a history of long-term use of alendronate. Because of the narrow medullary canal, we used 14 holes hybrid locking plate for the lateral aspect of the thigh to fix the fracture and 5 holes dynamic compression plate (instead of the intramedullary nail) in the anterior surface to double fix it, reducing the probability of device failure. With double plate fixation and discontinuation of alendronate, the complete union was achieved five months after surgery

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European Integration

10.3366/edinburgh/9781474455893.001.0001 ◽

2020 ◽

Author(s):

Johann P. Arnason

Keyword(s):

European Integration ◽

Eastern European ◽

The European Union ◽

Historical Processes ◽

History Of ◽

External Conditions ◽

Eastern European Countries ◽

Totalitarian Regimes ◽

The Eu

Different understandings of European integration, its background and present problems are represented in this book, but they share an emphasis on historical processes, geopolitical dynamics and regional diversity. The introduction surveys approaches to the question of European continuities and discontinuities, before going on to an overview of chapters. The following three contributions deal with long-term perspectives, including the question of Europe as a civilisational entity, the civilisational crisis of the twentieth century, marked by wars and totalitarian regimes, and a comparison of the European Union with the Habsburg Empire, with particular emphasis on similar crisis symptoms. The next three chapters discuss various aspects and contexts of the present crisis. Reflections on the Brexit controversy throw light on a longer history of intra-Union rivalry, enduring disputes and changing external conditions. An analysis of efforts to strengthen the EU’s legal and constitutional framework, and of resistances to them, highlights the unfinished agenda of integration. A closer look at the much-disputed Islamic presence in Europe suggests that an interdependent radicalization of Islamism and the European extreme right is a major factor in current political developments. Three concluding chapters adopt specific regional perspectives. Central and Eastern European countries, especially Poland, are following a path that leads to conflicts with dominant orientations of the EU, but this also raises questions about Europe’s future. The record of Scandinavian policies in relation to Europe exemplifies more general problems faced by peripheral regions. Finally, growing dissonances and divergences within the EU may strengthen the case for Eurasian perspectives.

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The natural history of pituitary apoplexy: long term follow-up study

Endocrine Abstracts ◽

10.1530/endoabs.65.p301 ◽

2019 ◽

Author(s):

Ayesha Shaikh ◽

Natasha Shrikrishnapalasuriyar ◽

Giselle Sharaf ◽

David Price ◽

Maneesh Udiawar ◽

...

Keyword(s):

Natural History ◽

Pituitary Apoplexy ◽

Follow Up Study ◽

Long Term Follow Up ◽

History Of

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Modelling of Moisture Movement in Wood during Outdoor Storage

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2001.6.1.15210 ◽

2001 ◽

Vol 6 (2) ◽

pp. 3-14 ◽

Cited By ~ 23

Author(s):

R. Baronas ◽

F. Ivanauskas ◽

I. Juodeikienė ◽

A. Kajalavičius

Keyword(s):

Experimental Data ◽

Finite Difference ◽

Climatic Conditions ◽

Two Dimensional ◽

Moisture Movement ◽

Finite Difference Technique ◽

Long Term Storage ◽

Space Formulation ◽

Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

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