The European Physical Journal H最新文献_第7页

The early years of quantum Monte Carlo (2): finite-temperature simulations 量子蒙特卡洛早期（2）：有限温度模拟

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-09-14 DOI: 10.1140/epjh/s13129-021-00026-5

Michel Mareschal

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How to model phase transitions? The changing approaches 1937–1970 如何建立相变模型？1937-1970年不断变化的方法

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-09-07 DOI: 10.1140/epjh/s13129-021-00024-7

Martin Niss

{"title":"How to model phase transitions? The changing approaches 1937–1970","authors":"Martin Niss","doi":"10.1140/epjh/s13129-021-00024-7","DOIUrl":"10.1140/epjh/s13129-021-00024-7","url":null,"abstract":"<div><p>The paper aims at characterising and documenting a fundamental change in how phase transitions were modelled microscopically in the period 1937–1970. At first, physicists took what will be called <i>a naturalistic approach</i> to phase transitions such as the condensation of gases and the Curie point of ferromagnets. Here the purpose was to explain the phenomenon in question, i.e., to show that a model exhibits the same features as the phenomenon. The scope of this approach was broad, as the goal was to account for several aspects of the phenomenon. The employed model should be very realistic and close to the foundational theory, be it classical or quantum mechanics. In the 1960s, the physicists used an alternative approach that they termed <i>a caricature approach. </i>This approach not only required explanation in the above sense but also understanding of the physical phenomenon, i.e. insights into why the phenomenon behaves as it does. The scope was limited to certain aspects of the phenomenon, such as the behaviour near the critical point. The caricature approach used a hierarchy of models, ranging from realistic ones over more simplified models to models that were mere caricatures of the system in question. Hence, the two approaches represent very different orientations when it comes to the purpose and scope, the organisation of the resulting theories, and what models are acceptable.\u0000</p></div>","PeriodicalId":791,"journal":{"name":"The European Physical Journal H","volume":"46 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78059265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Henry Cavendish and the effect of gravity on propagation of light: a postscript 亨利-卡文迪什与重力对光传播的影响：后记

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-09-02 DOI: 10.1140/epjh/s13129-021-00027-4

Karl-Heinz Lotze, Silvia Simionato

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Chronicle of the discovery of the back-bending phenomenon in atomic nuclei: a personal recollection 50 years on 发现原子核反弯曲现象纪事：50 年后的个人回忆

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-31 DOI: 10.1140/epjh/s13129-021-00023-8

Hans Ryde

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A road map for Feynman’s adventures in the land of gravitation 费曼万有引力探险路线图

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-26 DOI: 10.1140/epjh/s13129-021-00028-3

Marco Di Mauro, Salvatore Esposito, Adele Naddeo

{"title":"A road map for Feynman’s adventures in the land of gravitation","authors":"Marco Di Mauro, Salvatore Esposito, Adele Naddeo","doi":"10.1140/epjh/s13129-021-00028-3","DOIUrl":"10.1140/epjh/s13129-021-00028-3","url":null,"abstract":"<div><p>Richard P. Feynman’s work on gravitation, as can be inferred from several published and unpublished sources, is reviewed. Feynman was involved with this subject at least from late 1954 to the late 1960s, giving several pivotal contributions to it. Even though he published only three papers, much more material is available, beginning with the records of his many interventions at the Chapel Hill conference in 1957, which are here analyzed in detail, and show that he had already considerably developed his ideas on gravity. In addition, he expressed deep thoughts about fundamental issues in quantum mechanics which were suggested by the problem of quantum gravity, such as superpositions of the wave functions of macroscopic objects and the role of the observer. Feynman also lectured on gravity several times. Besides the famous lectures given at Caltech in 1962–1963, he extensively discussed this subject in a series of lectures delivered at the Hughes Aircraft Company in 1966–1967, whose focus was on astronomy and astrophysics. All this material allows to reconstruct a detailed picture of Feynman’s ideas on gravity and of their evolution until the late sixties. According to him, gravity, like electromagnetism, has quantum foundations, therefore general relativity has to be regarded as the classical limit of an underlying quantum theory; this quantum theory should be investigated by computing physical processes, as if they were experimentally accessible. The same attitude is shown with respect to gravitational waves, as is evident also from an unpublished letter addressed to Victor F. Weisskopf. In addition, an original approach to gravity, which closely mimics (and probably was inspired by) the derivation of the Maxwell equations given by Feynman in that period, is sketched in the unpublished Hughes lectures.</p></div>","PeriodicalId":791,"journal":{"name":"The European Physical Journal H","volume":"46 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75043396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Three Pathbreaking papers of 1966 revisited: their relevance to certain aspects of cosmological creation today 重温 1966 年的三篇开创性论文：它们与当今宇宙学创造的某些方面的相关性

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-17 DOI: 10.1140/epjh/s13129-021-00025-6

Jayant V. Narlikar

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The thermodynamics of black holes: from Penrose process to Hawking radiation 黑洞热力学：从彭罗斯过程到霍金辐射

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-05 DOI: 10.1140/epjh/s13129-021-00022-9

Carla Rodrigues Almeida

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Comment on Clebsch’s 1857 and 1859 papers on using Hamiltonian methods in hydrodynamics 评论克莱布施 1857 年和 1859 年关于在流体力学中使用汉密尔顿方法的论文

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-02 DOI: 10.1140/epjh/s13129-021-00014-9

Gérard Grimberg, Emanuele Tassi

{"title":"Comment on Clebsch’s 1857 and 1859 papers on using Hamiltonian methods in hydrodynamics","authors":"Gérard Grimberg, Emanuele Tassi","doi":"10.1140/epjh/s13129-021-00014-9","DOIUrl":"10.1140/epjh/s13129-021-00014-9","url":null,"abstract":"<div><p>The present paper is a companion of two translated articles by Alfred Clebsch, titled “On a general transformation of the hydrodynamical equations” and “On the integration of the hydrodynamical equations” (https://doi.org/10.1140/epjh/s13129-021-00015-8, https://doi.org/10.1140/epjh/s13129-021-00016-7). The originals were published in the “Journal für die reine and angewandte Mathematik” (1857 and 1859). Here we provide a detailed critical reading of these articles, which analyzes methods, and results of Clebsch. In the first place, we try to elucidate the algebraic calculus used by Clebsch in several parts of the two articles that we believe to be the most significant ones. We also provide some proofs that Clebsch did not find necessary to explain, in particular concerning the variational principles stated in his two articles and the use of the method of Jacobi’s Last Multiplier. When possible, we reformulate the original expressions by Clebsch in the language of vector analysis, which should be more familiar to the reader. The connections of the results and methods by Clebsch with his scientific context, in particular with the works of Carl Jacobi, are briefly discussed. We emphasize how the representations of the velocity vector field conceived by Clebsch in his two articles, allow for a variational formulation of hydrodynamics equations in the steady and unsteady case. In particular, we stress that what is nowadays known as the “Clebsch variables”, permit to give a canonical Hamiltonian formulation of the equations of fluid mechanics. We also list a number of further developments of the theory initiated by Clebsch, which had an impact on presently active areas of research, within such fields as hydrodynamics and plasma physics.</p></div>","PeriodicalId":791,"journal":{"name":"The European Physical Journal H","volume":"46 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76834407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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On a general transformation of the hydrodynamical equations 关于流体力学方程的一般变换

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-02 DOI: 10.1140/epjh/s13129-021-00015-8

A. Clebsch

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On the integration of the hydrodynamical equations 关于流体力学方程的整合

IF 0.8 4区物理与天体物理

The European Physical Journal H Pub Date : 2021-08-02 DOI: 10.1140/epjh/s13129-021-00016-7

A. Clebsch

引用次数: 0