Thesis (Ph. D.)--Harvard University, 1991. / Includes bibliographical references.

Thesis (Ph. D.)--Carleton University, 2001. / Includes bibliographical references (p. 150-161). Also available in electronic format on the Internet.

Thesis--Copenhagen. / Bibliography: p. 114-[119].

Unanimement considéré comme l’astronome le plus influent de l’entre-deux guerres, Arthur S. Eddington (1882-1944) a aussi investi le champ philosophique avec deux ouvrages majeurs, The Nature of the Physical World (1928) et The Philosophy of Physical Science (1939), mais également d’innombrables remarques au long de son œuvre considérable. Cette étude propose, à partir de l’ensemble des écrits d’Eddington, un portrait de sa philosophie. Envisagée dans son développement progressif d’abord, mettant tour à tour l’accent sur la synthèse, le symbole et la structure, dans ses interactions ensuite, dans ses racines philosophiques enfin. Se déploie peu à peu une conception originale de la nature et de la portée de la science physique, parfois déroutante mais non sans cohérence, à condition de la reconduire à ses intuitions originaires. / Arthur S. Eddington (1882-1944) certainly was the world’s most famous astronomer during the interwar period. He also plunged into philosophy and published a couple of major books,The Nature of the Physical World (1928) et The Philosophy of Physical Science (1939), as well as numerous remarks scattered along his works. Grounding its claims on the entirety of his writings, this study intends to sketch Eddington’s own philosophy. Its progressive development is firstly addressed, highlighting three essential themes, i. e. synthesis, symboland structure. Then are explored its interactions with both science and religion, and its rootsin terms of philosophical authors. An original conception of the nature and the scope of physical science slowly merges, sometimes upsetting but never without some kind of unity,provided its originating intuitions are finally discovered.

Orientador: Roberto de Andrade Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-02T08:27:27Z (GMT). No. of bitstreams: 1 JuradoHerrera_NuryIsabel_M.pdf: 1195976 bytes, checksum: ca21c9b45a3155f88dc2049fb4dd06b3 (MD5) Previous issue date: 2002 / Resumo: A presente dissertação introduz as idéias básicas para o surgimento da teoria da relatividade geral e sua posterior aplicação na construção de modelos cosmológicos relativísticos. Desta forma é apresentado um estudo histórico detalhado do desenvolvimento das cosmologias relativísticas no período compreendido entre 1917 e 1930, começando com o próprio Albert Einstein que, em 1917, propôs o primeiro modelo desta natureza, e encerrando a análise com Sir Arthur Eddington em 1930, cujo modelo, "Lemaître-Eddington", engloba os avanços da época. A partir do modelo de Lemaître-Eddington estudamos o papel fundamental que Eddington atribui à constante cosmológica, é neste item que suas concepções epistemológicas ficam mais evidenciadas, embora elas estejam presentes desde seus primeiros trabalhos. Discutimos também sua argumentação para calcular as constantes da natureza por métodos puramente teóricos. Acompanhamos o desenvolvimento do formalismo matricial que Eddington apresenta para escrever a equação de Dirac para o elétron e, a partir desta nova notação, descrevemos os argumentos utilizados por Eddington para encontrar o valor da constante de estrutura fina, a razão entre a massa do próton e do elétron, a razão entre a força elétrica e a força gravitacional entre um próton e um elétron, a razão entre um comprimento de tipo atômico e o raio de curvatura natural do espaço. Enfim, este estudo analisa as fases do trabalho científico de Eddington estabelecendo uma ponte entre seu trabalho cosmológico e seu trabalho epistemológico / Abstract:The present dissertation introduce the basic ideas of the beginning of the general theory of relativity and its later application on the construction of relativistic cosmological models. So we present here a detailed historical study of the development of the relativistic cosmologies in the period between 1917 and 1930, starting with Albert Einstein who, in 1917, proposed the first model of this kind, and finishing the analysis with Sir Arthur Eddington in 1930, whose model, "Lemaître-Eddington", incorporate the progresses of that time. From the model of "Lemaître-Eddington" we study the basic rule Eddington gives to the cosmological constant. It is in this topic his epistemological concepts become more evident, even though it is present since his ½rst works. We also discuss Eddington's argumentation to calculate the constants of the nature by pure theoretical methods. We follow the development of the matrix formalism that Eddington presents to write the Dirac equation for the electron and from this new notation we describe the logic used by Eddington to find the value of fine structure constant, the rate between the proton and electron mass, the rate between the electrical and gravitational force between a proton and an electron, the rate between an atomic length and the natural spacial curvature radius. So, this essay analyzes the diÿerent periods of Eddington's scientific work establishing one bridge between his cosmological work and his epistemological work / Mestrado / Física / Mestre em Física

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22251号 / 理博第4565号 / 新制||理||1655(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 嶺重 慎, 准教授 前田 啓一, 教授 長田 哲也 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

no / Over the last century there have been a number of proposals to ground both local and cosmic arrows of time: from the Second law to the Growing Block Universe, from Decoherence to Earman’s time-direction heresy. The latter proposal rejects the traditional association of the Second law of thermodynamics with arrows of time. But it seems that notions like entropy and related notions – phase space volumes and typicality – are not easily banned from discussions of temporal arrows. A close reading of Eddington’s thinking on these questions reveals that his views underwent a considerable development. In particular Eddington abandoned his identification of the arrows of time with the increase in entropy and began to see the Second law as a criterion for temporal arrows. In the process, Eddington also developed an argument against Loschmidt’s reversibility objections, in terms of an expanding universe. This latter argument brings his contribution close to contemporary thinking in terms of Liouville’s theorem, the topology of phase space and typicality arguments. Their reliability to deliver arrows of time will therefore be considered. Are there arrows of time? This question is related to the epistemological views of both Eddington and Wheeler. They insisted on the role of inferences in scientific thinking. Physical reality was to be inferred from data (Eddington) or information (Wheeler) about the physical universe. The paper will conclude that the arrows of time are equally to be regarded as conceptual inferences from various physical criteria – not just entropy – which the universe makes available to us.

Cette thèse traite des aspects astrophysiques de la détection directe (DD) de matière noire sous forme de WIMPs. On se concentre sur les contraintes observationnelles des quantités astrophysiques qui influent sur l'interprétation des résultats expérimentaux de DD.On revoit tout d'abord le formalisme de la DD et on résume les résultats expérimentaux les plus importants ainsi que les méthodes statistiques généralement utilisés pour interpréter les données. On reproduit ensuite les limites expérimentales sur la section efficace spin-indépendante. On résume l'ensemble des hypothèses astrophysiques couramment utilisées dans le modèle de halo standard et on décrit l'influence de ses paramètres sur les limites.Pour inscrire la DD dans un cadre plus général, on résume les concepts les plus importants de la dynamique Galactique. En particulier, on revoit comment modéliser la Galaxie avec des modèles de masse, tout en soulignant les relations entre les différentes quantités astrophysiques. On décrit des procédures qui permettent d'obtenir des distributions dans l'espace des phases de la matière noire qui soient consistantes avec un profil de matière noire et un potentiel Galactique donné. La plus simple procédure étant basée sur l'équation d'Eddington, on discute ses limites d'applicabilité. On revoit dans les détails la littérature récente concernant les déterminations et les incertitudes des quantités astrophysiques liées à la DD et des paramètres Galactiques fondamentaux.Dans la dernière partie de la thèse on s'intéresse aux estimations récentes de la vitesse d'échappement publiées par la collaboration RAVE. On étudie dans les détails les implications de ces résultats sur les expériences de DD. Pour cela on prends en compte les corrélations entre les quantités astrophysiques importantes pour la DD, et en assumant le modèles de masse de RAVE on calcule la distribution de matière noire dans l'espace des phases avec l'équation d'Eddington. Du fait des valeurs plus élevés de la densité locale de matière noire, cette procédure conduit à des limites plus contraignantes par rapport a celles standards. / This thesis deals with the astrophysical aspects of the direct detection of WIMP dark matter (DMDD). In particular, it focuses on the observational constraints on the astrophysical quantities relevant for DMDD, which impact on the interpretation of the experimental results.We review the formalism of DMDD and we summarize some of the main experimental results in this domain and the statistical methods usually employed to interpret the data, reproducing the associated constraints on the parameter space relevant for spin-independent WIMP-nucleon interaction. We summarize the set of astrophysical assumptions usually employed, the Standard Halo Model, and we point out the impact of variations in its parameters on such limits.We outline the main concepts of the dynamics of our galaxy that allow to put the astrophysics related to DMDD in a wider framework. In particular, we review the description of the Galaxy through Milky Way mass models (MWMM), pointing out how the astrophysical quantities are related. We describe some procedures to obtain dark matter phase-space distributions consistent with given dark matter profile and Galactic potential, the simplest being Eddington equation, of which we discuss the limits of applicability. We review in detail the recent literature on the main determinations and uncertainties of the astrophysical quantities relevant for DMDD and of the fundamental Galactic parameters.In the most original part of this thesis we focus on the recent estimates of the local Galactic escape speed published by the RAVE collaboration. We study in detail the implications of these results for the spin-independent interpretation of DMDD experiments. We take into account the correlations between the astrophysical quantities relevant for DMDD calculations, and from the assumed MWMM we compute the dark matter phase-space distribution using Eddington equation, which provides a self-consistent physical connection between the two. This procedure leads to more constraining exclusion curves with respect to the standard ones, due to higher values of the local dark matter density.

In this dissertation I analyze Sir Arthur Eddington's statistical theory as developed in the first six chapters of his posthumously published Fundamental Theory. In particular I look at the mathematical structure, philosophical implications, and relevancy to modern physics. This analysis is the only one of Fundamental Theory that compares it to modern quantum field theory and is the most comprehensive look at his statistical theory in four decades. Several major insights have been made in this analysis including the fact that he was able to derive Pauli's Exclusion Principle in part from Heisenberg's Uncertainty Principle. In addition the most profound general conclusion of this research is that Fundamental Theory is, in fact, an early quantum field theory, something that has never before been suggested. Contrary to the majority of historical reports and some comments by his contemporaries, this analysis shows that Eddington's later work is neither mystical nor was it that far from mainstream when it was published. My research reveals numerous profoundly deep ideas that were ahead of their time when Fundamental Theory was developed, but that have significant applicability at present. As such this analysis presents several important questions to be considered by modern philosophers of science, physicists, mathematicians, and historians. In addition it sheds new light on Eddington as a scientist and mathematician, in part indicating that his marginalization has been largely unwarranted.