The European Physical Journal H最新文献

We analyzed remarkable stories linked to the famous Anatoly Vlasov equations in plasma physics. Their creation, modification, and application are interesting from the scientific viewpoint. We also show the relations between those equations dealing with electromagnetism and analogous Jeans equations describing, in particular, gravitational instability in astrophysics. The second half of the essay is devoted to the controversies and political struggle in Soviet (before 1991) and Russian (after 1991) physical communities related to Vlasov’s personality, career, and posthumous recognition. The never-ending destructive influence of the Russian totalitarianism on science is demonstrated.

We present a translation of the 1933 paper by R. Fürth in which a profound analogy between quantum fluctuations and Brownian motion is pointed out. Fürth highlights the existence of uncertainty relations involving the variance of a statistically conserved quantity of a non-equilibrium thermodynamic indicator and the variance of the corresponding current velocity. The phenomenon is entirely classical and traces back to the effect of a fluctuating environment on a measured system. In some sense, Fürth’s paper also opened the way to the stochastic methods of quantization developed almost 30 years later by Edward Nelson and others.

The development and evolution of the “Einstein–Æther Theory” (Æ-theory) shows that there is a field in cosmology where the word ether is being used again. It is unclear, however, whether this æther may be regarded in continuation with previous ethers, or it is an altogether new entity. The main goal of this paper is to understand the nature of this new ether in the context of previous instances of this scientific object. In order to do so, we shall first give a brief historical account of the distinct uses the word had assumed in the late nineteenth and early twentieth centuries, before its demise. Then, we shall describe the major attempts to revive the ether over the last century, focusing on the last endeavor: the Æ-theory. In this article, we do not intend to support or reject this new use of the word, but to stress the complexity of establishing a consistent historical narrative of some scientific objects like the ether.

The nature of light, the existence of magnetism, and the physical meaning of a vacuum are the problems so deeply related to philosophy that they have been discussed for thousands of years. In this paper, we concentrate ourselves on a question that concerns the three of them: does light speed in a vacuum change when a magnetic field is present? The experimental answer to this fundamental question has not yet been given even if it has been stated in modern terms for more than a century. To fully understand the importance of such a question in physics, we review the main facts and concepts from the historical point of view.

The Inter-University Centre for Astronomy and Astrophysics (IUCAA) is the second Inter-University Centre established by the Government of India for promotion of astronomy and astrophysical research. In this article, the historical development, as well as the motivation, for establishing IUCAA has been discussed which comprises of the period 1988–1993, i.e. the first 5 years. A glimpse of research work in pre- and post-colonial era in India has also been presented to have a holistic view of the genesis.

The history of the Institute of Physics at the University of Florence is traced from the beginning of the twentieth century, with the arrival of Antonio Garbasso as Director (1913), to the 1960s. Thanks to Garbasso’s expertise, not only did the Institute gain new premises on Arcetri hill, where the Astronomical Observatory was already located, but it also formed a brilliant group of young physicists made up of Enrico Fermi, Franco Rasetti, Enrico Persico, Bruno Rossi, Gilberto Bernardini, Daria Bocciarelli, Lorenzo Emo Capodilista, Giuseppe Occhialini and Giulio Racah, who were engaged in the emerging fields of Quantum Mechanics and cosmic rays. This Arcetri School disintegrated in the late 1930s for the transfer of its protagonists to chairs in other universities, for the environment created by the fascist regime and, to some extent, for the racial laws. After the war, the legacy was taken up by some students of this school who formed research groups in the field of nuclear physics and elementary particle physics. As far as Theoretical Physics was concerned, after the Fermi and Persico periods these studies enjoyed a new expansion towards the end of the 1950s, with the arrival of Giacomo Morpurgo and above all, that of Raoul Gatto, who created the first real Italian school of Theoretical Physics at Arcetri.

The JADE experiment was one of five large detector systems taking data at the electron–positron collider PETRA, from 1979 to 1986, at (e^+e^-) annihilation centre-of-mass energies from 12 to 46.7 GeV. The forming of the JADE collaboration, the construction of the apparatus, the most prominent physics highlights, and the post-mortem resurrection and preservation of JADE’s data and software are reviewed.

We give a detailed description of the May 16, 1931, lecture by Albert Einstein on cosmology at Oxford University. In this lecture, Einstein discussed his cosmological model of 1931, a model in which the universe was assumed to expand from zero size to a maximum size and then collapse back again. We use information from the two blackboards that Einstein filled for the lecture and intertwine it with a detailed newspaper transcript of what Einstein said concurrently in German. We thereby present a line-by-line explanation of what was conveyed on the blackboards visually and, in an approximate way, what was concurrently conveyed verbally by Einstein. Even though very few in the audience that day would qualify, we assume the point of view of a sufficiently prepared member of the audience. Our discussion is informed by a summary pamphlet that was handed out by the organizers of the talks. We also describe some mistakes that Einstein made in his talk, issues surrounding the successful preservation of one of the two blackboards, as well as some aspects of Einstein’s cosmological thinking after the talk.

In this essay, we aim to illustrate how Martin Karplus and his research group effectively set in motion the engine of molecular dynamics (MD) simulations of biomolecules. This process saw its prodromes between 1969 and the early 1970s with Karplus’ landing in biology, a transition that came to fruition with the treatment of 11-cis-retinal photoisomerization and the development of an allosteric model to account for the mechanism of cooperativity in hemoglobin. In 1977, J. Andrew McCammon, Bruce Gelin, and Martin Karplus published an article in Nature reporting the MD simulation of bovine pancreatic trypsin inhibitor (BPTI). This publication helped initiate the merger of computational statistical mechanics and biochemistry, a process that Karplus undertook at a later stage and whose beginnings we propose to reconstruct in this article through unpublished accounts of the key people who participated in this endeavor.

Samuil Kaplan (1921–1978) was a productive and famous astrophysicist. He was affiliated with a number of scientific centers in different cities of former Soviet Union. The earliest 13 years of his career, namely in the 1948–1961 years, he worked in Lviv University in Ukraine (then it was called the Ukrainian Soviet Socialist Republic). In the present paper, the Lviv period of his life and scientific activity is described on the basis of archival materials and his published studies. Kaplan arrived in Lviv in June 1948, at the same month when he obtained the degree of Candidate of science. He was a head of the astrophysics sector at the Astronomical Observatory of the University, was a professor of department for theoretical physics as well as the founder and head of a station for optical observations of artificial satellites of Earth. He was active in the organization of the astronomical observational site outside of the city. During the years in Lviv, Kaplan wrote more than 80 articles and 3 monographs in 9 areas. The focus of his interests at that time was on stability of circular orbits in the Schwarzschild field, on white dwarf theory, on space gas dynamics, and cosmic plasma physics, and turbulence, on acceleration of cosmic rays, on physics of interstellar medium, on physics and evolution of stars, on cosmology and gravitation, and on optical observations of Earth artificial satellites. Some of his results are fundamental for development of theory in these fields as well as of observational techniques. The complete bibliography of his works published during the Lviv period is presented. Respective scientific achievements of Samuil Kaplan are reviewed in the light of the current state of research in these areas.