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The blackbody spectrum "half-power points" are used to assign effective Q "quality factor" values that are found to be less than unity whether frequency or wavelength scaling is used. A comparison with values for coherent oscillators is made. This exercise blends two of Kirchhoff's interests, and is instructive in its own right, as it bridges the often mutually exclusive engineering and scientific disciplines.

This paper investigates the formation and propagation of wavefunction `branches' through the process of entanglement with the environment. While this process is a consequence of unitary dynamics, and hence significant to many if not all approaches to quantum theory, it plays a central role in many recent articulations of the Everett or `many worlds' interpretation. A highly idealized model of a locally interacting system and environment is described, and investigated in several situations in which branching occurs, including those involving Bell inequality violating correlations; we illustrate how any non-locality is compatible with the locality of the dynamics. Although branching is particularly important for many worlds quantum theory, we take a neutral stance here, simply tracing out the consequences of a unitary dynamics. The overall goals are to provide a simple concrete realization of the quantum physics of branch formation, and especially to emphasise the compatibility of branching with relativity; the paper is intended to illuminate matters both for foundational work, and for the application of quantum theory to non-isolated systems.

Philosophers of science commonly connect ontology and science, stating that these disciplines maintain a two-way relationship: on the one hand, we can extract ontology from scientific theories; on the other hand, ontology provides the realistic content of our scientific theories. In this article, we will critically examine the process of naturalizing ontology, i.e., confining the work of ontologists merely to the task of pointing out which entities certain theories commit themselves to. We will use non-relativistic quantum mechanics as a case study. We begin by distinguishing two roles for ontology: the first would be characterized by cataloging existing entities according to quantum mechanics; the second would be characterized by establishing more general ontological categories in which existing entities must be classified. We argue that only the first step is available for a naturalistic approach; the second step not being open for determination or anchoring in science. Finally, we also argue that metaphysics is still a step beyond ontology, not contained in either of the two tasks of ontology, being thus even farther from science., Comment: Forthcoming in THEORIA, Special Issue: "Quantum Mechanics and Reality'', 2024

Berta Karlik was an Austrian physicist who was not only among the early radioactivity researchers and nuclear physicists in Vienna, but also pioneered a woman's academic career in Austria. She was the first woman at the University of Vienna to acquire the venia legendi in physics, and the first full professor at a philosophical faculty in Austria. For almost thirty years she was the head of the Institute for Radium Research of the Austrian Academy of Sciences., Comment: 12 pages, 5 figures

Yuri L'vovich Klimontovich (28.09.1924--26.10.2002) was an outstanding theoretical physicist who made major contributions to kinetic theory. On the occasion of his 100th birthday we recall his main scientific achievements.

According to a particular interpretation of quantum mechanics, the causal role of human consciousness in the measuring process is called upon to solve a foundational problem called the "measurement problem". Traditionally, this interpretation is tied up with the metaphysics of substance dualism. As such, this interpretation of quantum mechanics inherits the dualist's mind-body problem. Our working hypothesis is that a process-based approach to the consciousness causes collapse interpretation (CCCI) -- leaning on Whitehead's solution to the mind-body problem -- offers a better metaphysical understanding of consciousness and its role in interpreting quantum mechanics. This article is the kickoff for such a research program in the metaphysics of science., Comment: Forthcoming in Manuscrito vol. 47, n.1, 2024. Special issue: "Scientific Process Ontology and Metaphysics". Url: https://www.scielo.br/j/man/i/2024.v47n1

It is universally believed that with his 1905 paper ``Does the inertia of a body depend on its energy content?" Einstein first demonstrated the equivalence of mass and energy by making use of his new special theory of relativity. In the final step of that paper, however, Einstein equates the kinetic energy of a body to its Newtonian value, indicating that his result is at best a low-velocity approximation. Today, several characters debate whether a mid-nineteenth century physicist, employing only Galilean and pre-Maxwellian physics could plausibly arrive at the celebrated result. In other words, is Einsteinian relativity necessary to derive ${\mathcal E}=mc^2$?, Comment: 33 pages, 3 figures

We will argue that a phenomenological analysis of consciousness, similar to that of Husserl, shows that the effects of phenomenal qualities shape our perception of the world. It also shows the way the physical and mathematical sciences operate, allowing us to accurately describe the observed regularities in terms of communicable mathematical laws. The latter say nothing about the intrinsic features of things. They only refer to the observed regularities in their behaviors, providing rigorous descriptions of how the universe works, to which any viable ontology must conform. Classical mechanistic determinism limits everything that can occur to what happens in an instant and leaves no room for novelty or any intrinsic aspect that is not epiphenomenal. The situation changes with quantum probabilistic determinism if one takes seriously the ontology that arises from its axioms of objects, systems in certain states, and the events they produce in other objects. As Bertrand Russell pointed out almost a century ago, an ontology of events, with an internal phenomenal aspect, now known as panprotopsychism, is better suited to explaining the phenomenal aspects of consciousness. The central observation of this paper is that many objections to panpsychism and panprotopsychism, which are usually called the combination problem, arise from implicit hypotheses based on classical physics about supervenience. These are inappropriate at the quantum level, where an exponential number of emergent properties and states arise. The analysis imposes conditions on the possible implementations of quantum cognition mechanisms in the brain., Comment: 18 pages, no figures

Noel Frederick Smyth (NFS), a Fellow of the Australian Mathematical Society and a Professor of Nonlinear Waves in the School of Mathematics at the University of Edinburgh, passed away on February 5, 2023. NFS was a prominent figure among applied mathematicians who worked on nonlinear wave theory in a broad range of areas. Throughout his academic career, which spanned nearly forty years, NFS developed mathematical models, ideas, and techniques that have had a large impact on the understanding of wave motion in diverse media. His major research emphasis primarily involved the propagation of solitary waves, or solitons, and dispersive shock waves, or undular bores, in various media, including optical fibers, liquid crystals, shallow waters and atmosphere. Several approaches he developed have proven effective in analyzing the dynamics and modulations of related wave phenomena. This tribute in the journal of Wave Motion aims to provide a brief biographical sketch of NFS, discuss his major research achievements, showcase his scientific competence, untiring mentorship and unwavering dedication, as well as share final thoughts from his former students, colleagues, friends, and family. The authors had a special connection with NFS on both on personal and professional levels and hold deep gratitude for him and his invaluable work. In recognition of his achievements in applied mathematics, Wave Motion hosts a Special Issue entitled "Modelling Nonlinear Wave Phenomena: From Theory to Applications," which presents the recent advancements in this field., Comment: To appear in a Special Issue in Wave Motion

In his article in Science, Nicolas Gisin claimed that quantum correlations emerge from outside space time. We explain that they are due to space time symmetries. This paper is a critical review of metaphysical conclusions found in many recent articles. It advocates the importance of contextuality, Einstein causality and global symmetries. Bell tests allow only rejecting probabilistic coupling provided by a local hidden variable model, but they do not justify metaphysical speculations about quantum nonlocality and objects which know about each other state, even when separated by large distances. The violation of Bell inequalities in physics and in cognitive science can be explained using the notion of Bohr contextuality. If contextual variables, describing varying experimental contexts, are correctly incorporated into a probabilistic model, then the Bell and CHSH inequalities cannot be proven and nonlocal correlations may be explained in an intuitive way. We also elucidate the meaning of statistical independence assumption incorrectly called free choice, measurement independence or no conspiracy. Since correlation does not imply causation, the violation of statistical independence should be called contextuality and it does not restrict the experimenter freedom of choice. Therefore, contrary to what is believed, closing the freedom of choice loophole does not close the contextuality loophole., Comment: 17 pages, 97 references

The onset and the development of the concept of exchange force in quantum physics are historically reconstructed, starting from Heisenberg's seminal contributions in 1926 and going through the great developments in nuclear physics, which allowed the emergence of the idea of force mediating virtual quanta. Although most of such work was performed in Europe, the last and decisive effort in this long path was carried out by Japanese scientists in the 1930s. This is the main focus of the present work, which retraces the achievements of Yukawa and Tomonaga, whose results and mutual interactions are carefully analyzed and related to those of European physicists., Comment: 37 pages, no figures, Springer Nature style, submitted for publication

Theoretical physics suffered a major loss with the death of my dear friend Jan Zaanen on January 18. This note is my remembrance of him.

In this paper, we investigate the possibility of explaining nonclassical correlations between two quantum systems in terms of quantum interferences between collective states of the two systems. We achieve this by mapping the relations between different measurement contexts in the product Hilbert space of a pair of two-level systems onto an analogous sequence of interferences between paths in a single-particle interferometer. The paradoxical relations between different measurement outcomes can then be traced to the distribution of probability currents in the interferometer. We show that the relation between probability currents and correlations can be represented by continuous conditional (quasi)probability currents through the interferometer, given by weak values; the violation of the noncontextual assumption is expressed by negative conditional currents in some of the paths. Since negative conditional currents correspond to the assignment of negative conditional probabilities to measurements results in different measurement contexts, the necessity of such negative probability currents represents a failure of noncontextual local realism. Our results help to explain the meaning of nonlocal correlations in quantum mechanics, and support Feynman's claim that interference is the origin of all quantum phenomena., Comment: 10 pages, 4 figures. Comments welcome!

I argue that research in physics operates under an implicit community philosophy, and I offer a definition I think physicists would accept, by and large. I compare this definition to what philosophers, sociologists, and historians of science, with physicists, say we are doing., Comment: I plan to publish in a journal to be chosen, but seek to check first if the presence in arXiv generates any feedback. I would add a cross-reference to physics.fundamental if it existed

We examine the justification for taking the Event Horizon Telescope's famous 2019 image to be a reliable representation of the region surrounding a black hole. We argue that it takes the form of a robustness argument, with the resulting image being robust across variation in a range of data-analysis pipelines. We clarify the sense of "robustness" operating here and show how it can account for the reliability of astrophysical inferences, even in cases -- like the EHT -- where these inferences are based on experiments that are (for all practical purposes) unique. This has consequences far beyond the 2019 image., Comment: 32 pages, forthcoming in Philosophy of Physics

This article uses the existing literature on the panpsychist combination problem as a starting point to think about how to address a structurally similar combination problem in relational quantum mechanics. I note some similarities and differences between the two problems, and I consider various proposed solutions to the panpsychist problem, assessing the prospects for a similar solution in the context of RQM. I argue that overall the prospects for solving RQM's combination problem look better for RQM with cross-perspective links than for orthodox versions of RQM.

Antonie (Anton) Pannekoek (1873-1960) is remembered as one of the initiators of the field of stellar atmospheres. A second part of his research concerned Galactic astronomy. He was convinced that the sidereal system was built up of clouds of stars in a smooth, low-density stratum. In addition there were dark clouds together with streaks with little or no extinction in between. Pannekoek looked at bright star clouds and estimated their distance from their contribution to star counts. He found values of tens of kpc, which would mean their distribution was similar in extent to that of Shapleys globular cluster system. Later he had to reduce his distance by a factor over two, and later still retract the method. He developed a rigorous method of estimating distances of dark clouds from modeling star counts off and on the cloud, preceding Wolf's quick and dirty method. He should have received more credit for this. He started isophotal maps of the northern and southern Milky Way, first from visual observations, later from photographic surface photometry using out-of-focus exposures. I compare Pannekoeks maps with detailed photographic surface photometry of the south by the group in Bochum and to the almost all-sky mapping by the Pioneer 10 spacecraft, free of zodiacal light, from beyond the asteroid belt. This shows Panneloeks maps to be surprisingly accurate. The legacy of Pannekoek in the area of Galactic research consists of his mapping of the structure of the nearby part of the Galaxy, the distances of dark clouds, and isophotal maps of the Milky Way. His other contributions turned out inconclusive or wrong as a result of his conviction, resulting from his many years of observing and mapping the Milky Way, that the nearby distribution is characterized primarily by more or less isolated clouds of stars and by dust restricted to isolated dark clouds and streaks., Comment: 92 pages, 32 figures, 4 tables. This paper has been accepted for publication in the March issue by the Journal of Astronomical History and Heritage. For a version with high-resolution figures please go to the my homepage, where a link will be provided

I present aspects of causal set theory (a research programme in quantum gravity) as being en route to achieving a reduction of Lorentzian geometry to causal sets. I take reduction in philosophers' sense; and I argue that the prospects are good for there being a reduction of the type envisaged by Nagel. (I also discuss the prospects for the stronger functionalist variant of Nagelian reduction, that was formulated by Lewis.) One main theme will be causal set theory's use of a physical scale (viz. the Planck scale) to formulate how it recovers a Lorentzian manifold. This use illustrates various philosophical topics relevant to reduction, such as limiting relations between theories, and the role of analogy. I also emphasise causal set theory's probabilistic method, viz. Poisson sprinkling: which is used both for formulating the reduction and for exploring its prospects., Comment: 31 pages, no Figures. Forthcoming in 'Time and Timelessness in Fundamental Physics and Cosmology', edited by S. De Bianchi, M. Forgione and L. Marongiu; Springer

Our representation of the Universe is built with sequences of symbols, numbers, operators, rules and undecidable propositions defining our mathematical truths, represented either by classical, quantum and probabilistic Turing Machines containing intrinsic randomness. Each representation is at all effects a physical subset of the Universe, a metastructure of events in space and time, which actively participate to the evolution of the Universe as we are internal observers. The evolution is a deterministic sequence of local events, quantum measurements, originated from the local wavefunction collapse of the complementary set of the observers that generate the local events in the Universe. With these assumptions, the Universe and its evolution are described in terms of a semantically closed structure without a global object-environment loss of decoherence as a von Neumann's universal constructor with a semantical abstract whose structure cannot be decided deterministically a-priori from an internal observer. In a semantically closed structure the realization of a specific event writing the semantical abstract of the constructor is a problem that finds a "which way" for the evolution of the Universe in terms of a choice of the constructor's state in a metastructure, the many-world Everett scenario from the specific result of a quantum measurement, a classical G\"odel undecidable proposition for an internal observer, exposing the limits of our description and possible simulation of the Universe., Comment: 27 pages

We describe the results in the trigonometry of tetrahedra obtained by Joseph Wolstenholme in the last few years of his life. 'The late Professor Wolstenholme, M.A., Sc.D., shortly before his death, handed to me a scrap of paper, on which he had hastily scratched the following equation in tetrahedra, saying he had proved it ...' (Richardson, 1897).

We consider conservation of momentum in AQUAL, a field-theoretic extension to Modified Newtonian Dynamics (MOND). We show that while there is a sense in which momentum is conserved, it is only if momentum is attributed to the gravitational field, and thus Newton's third law fails as usually understood. We contrast this situation with that of Newtonian gravitation on a field theoretic formulation. We then briefly discuss the situation in TeVeS, a relativistic theory that has AQUAL as a classical limit., Comment: We have become aware of a serious error in the arguments of section III.B. This error is such that the main claim of that section does not follow. Since these arguments are integral to the thesis of the manuscript, we withdraw the manuscript at this time while working on corrections. The authors are grateful to Moti Milgrom for kindly pointing out the error

The first Edition of this book was released in 2000, just before the symposium ``Thirty Years of Supersymmetry'' was held at the William I. Fine Theoretical Physics Institute (FTPI) of the University of Minnesota. Founders and trailblazers of supersymmetry descended on FTPI, as well as a large crowd of younger theorists deeply involved in research in this area. Since then 23 years have elapsed and significant changes happened in supersymmetry (SUSY). Its history definitely needs an update. Such an update is presented below. The Second Edition of the revised collection will be released in 2024., Comment: 16 pages, 7 figures. V. 2: A few references added; some minor insertions added

Did the papacy tacitly permit the circulation of an explicitly Copernican book in 1660? One scholar has recently argued that it did. A close analysis of a unique illustration from that book, Andreas Cellarius's atlas Harmonia Macrocosmica, illuminates this argument. This is because the illustration, a diagram showing the relative sizes of the sun, moon, planets, and stars, was among the material reviewed (at the request of the book's publisher) by the Holy Office prior to the book's publication and was pro-Copernican., Comment: 15 pages, 5 figures

Cornerstones of the Cellular Automaton Interpretation of Quantum Mechanics are its ontological states that evolve by permutations, in this way never creating would-be quantum mechanical superposition states. We review and illustrate this with a classical Ising spin chain. It is shown that it can be related to the Weyl equation in the continuum limit. Yet, the model of discrete spins or bits unavoidably becomes a model of qubits by generating superpositions, if only slightly deformed. We study modifications of its signal velocity which, however, do not relate to mass terms. To incorporate the latter, we consider the Dirac equation in 1+1 dimensions and sketch an underlying discrete deterministic "necklace of necklaces" automaton that qualifies as ontological., Comment: 17 pages, 1 figure; v2 with 7 refs added to Sec 1; accepted for publ in Int J Qu Info

In recent years, the question of the reliability of Machine Learning (ML) methods has acquired significant importance, and the analysis of the associated uncertainties has motivated a growing amount of research. However, most of these studies have applied standard error analysis to ML models, and in particular Deep Neural Network (DNN) models, which represent a rather significant departure from standard scientific modelling. It is therefore necessary to integrate the standard error analysis with a deeper epistemological analysis of the possible differences between DNN models and standard scientific modelling and the possible implications of these differences in the assessment of reliability. This article offers several contributions. First, it emphasises the ubiquitous role of model assumptions (both in ML and traditional Science) against the illusion of theory-free science. Secondly, model assumptions are analysed from the point of view of their (epistemic) complexity, which is shown to be language-independent. It is argued that the high epistemic complexity of DNN models hinders the estimate of their reliability and also their prospect of long-term progress. Some potential ways forward are suggested. Thirdly, this article identifies the close relation between a model's epistemic complexity and its interpretability, as introduced in the context of responsible AI. This clarifies in which sense, and to what extent, the lack of understanding of a model (black-box problem) impacts its interpretability in a way that is independent of individual skills. It also clarifies how interpretability is a precondition for assessing the reliability of any model, which cannot be based on statistical analysis alone. This article focuses on the comparison between traditional scientific models and DNN models. But, Random Forest and Logistic Regression models are also briefly considered., Comment: Minor clarifications in Sec. 4.1. Misleading table removed

Algebraic quantum field theory (AQFT) puts forward three "causal axioms" that aim to characterize the theory as one that implements relativistic causation: the spectrum condition, microcausality, and primitive causality. In this paper, I aim to show, in a minimally technical way, that none of them fully explains the notion of causation appropriate for AQFT because they only capture some of the desiderata for relativistic causation I state or because it is often unclear how each axiom implements its respective desideratum. After this diagnostic, I will show that a fourth condition, local primitive causality (LPC), fully characterizes relativistic causation in the sense of fulfilling all the relevant desiderata. However, it only encompasses the virtues of the other axioms because it is implied by them, as I will show from a construction by Haag and Schroer (1962). Since the conjunction of the three causal axioms implies LPC and other important results in QFT that LPC does not imply, and since LPC helps clarify some of the shortcomings of the three axioms, I advocate for a holistic interpretation of how the axioms characterize the causal structure of AQFT against the strategy in the literature to rivalize the axioms and privilege one among them., Comment: Forthcoming in Studies in History and Philosophy of Science

Many scientists view science as value-free, despite the fact that both epistemic and non-epistemic values structure scientific inquiry. Current ethics training usually focuses on transmitting knowledge about high-level ethical concepts or rules and is widely regarded as ineffective. We argue that ethics training will be more effective at improving ethical decision making if it focuses on connecting values to science. We pull from philosophy and psychology to define ethical decision making using the Four Component Model. This model states that in order to make an ethical decision someone must consider four components: moral sensitivity, moral reasoning, moral motivation, and moral implementation. We formed a moderated fellowship of fourteen science faculty from different disciplines who met for ten sessions over the course of a year, where they discussed the values embedded in different scientific norms. We then conducted interviews before and after the year-long fellowship that involved guided reflection of scenarios where there was some kind of ethical misconduct where the scientific practice required value judgements (e.g using unpublished data in their own work). We looked at how the fellowship affected the scientists' ability to recognize ethical dimensions regarding the scenarios. We found that this fellowship improved moral sensitivity, but their moral reasoning does not improve. We outlined our approach on how to look at scientists' ethical decision making and made recommendations on how to improve our approach. This work can inform future ethical training to align better with what scientists value and introduce useful concepts from philosophy and psychology to education research in physics.

This paper addresses the central question of what a coherent concept of probability might look like that would do justice to both classical probability theory, axiomatized by Kolmogorov, and quantum theory. At a time when quanta are receiving increased and expanded attention -- think, for example, of the advances in quantum computers or the promises associated with this new technology (National Academies of Sciences: Engineering, and Medicine, 2019) -- an adequate interpretation of probability, which is no less important, should be given due attention, particularly with regard to quantum theory., Comment: in German language

I describe aspects of my life in physics: the name I publish under, great physicists I have known, how I got into quantum foundations, what role I've played in it. My form is autobiographical, but my personal experience may illustrate what it was like being a physicist over the past 60 years. I offer some offbeat ways of thinking about some orthodox physics., Comment: 17 pages, no figures

The issue of non-locality in quantum mechanics can potentially be resolved by considering relativistically covariant diffusion in four-dimensional spacetime. Stochastic particles described by the Klein-Gordon equation are shown to undergo a classical diffusion process in spacetime coordinates, which is seen by transforming the quantum Cauchy-momentum equations to a Lagrangian frame of reference. Since the quantum potential term is removed under this transformation, the equations for momentum propagation along particle trajectories assume a classical form. A local stochastic de Broglie-Bohm interpretation for the Klein-Gordon system can subsequently be derived. We also introduce the concept of momentum equivariance to replace the second-order Bohm-Newton equations of motion, which break down due to non-linear terms of the stochastic Lagrangian derivative.

We introduce a transformation of the quantum phase $S'=S+\frac{\hbar}{2}\log\rho$, which converts the deterministic equations of quantum mechanics into the Lagrangian reference frame of stochastic particles. We show that the quantum potential can be removed from the transformed quantum Hamilton-Jacobi equations if they are solved as stochastic Hamilton-Jacobi-Bellman equations. The system of equations provide a local description of quantum mechanics, which is enabled by the inherently retrocausal nature of stochastic Hamilton-Jacobi-Bellman equations. We also investigate the stochastic transformation of the classical system, where is it shown that quantum mechanics with the quantum potential reduced by a factor of $\frac{1}{2}$ has a classical representation, which may have interesting implications. Finally, we discuss the notion of a subsystem correspondence principle, which constrains the ontology of the total quantum system.

The Nernst heat theorem is probed from purely thermodynamic arguments connected with the second law of thermodynamics, and alien to the vanishing of the specific heats, or to the unattainability of the zeroth isotherm. If the proof is accepted the second law of thermodynamics would extend its applicability and the third postulate of thermodynamics would be narrowed to the fact that the entropy of a finite-density, chemically homogeneous body must not be negative. -- -- Se demuestra el teorema de Nernst a partir de argumentos exclusivamente termodin\'amicos que se extraen del segundo principio, y que son ajenos a la anulaci\'on de los calores espec\'ificos o a la inaccesibilidad de la isoterma cero. Si se acepta la demostraci\'on, entonces el segundo principio extender\'ia su rango de aplicabilidad y el tercer principio quedar\'ia reducido al hecho de que la entrop\'ia de un cuerpo de densidad finita y quimicamente homog\'eneo no puede ser negativa., Comment: ENG: 1600 words; 1 figure. ESP: 1800 palabras, 1 figura

The atomic bomb uses fission of heavy elements to produce a large amount of energy. It was designed and deployed during World War II by the United States military. The first test of an atomic bomb occurred in July of 1945 in New Mexico and was given the name Trinity; this test was not declassified until 1949. In that year Geoffrey Ingram Taylor released two papers, detailing his process in calculating the energy yield of the atomic bomb from pictures of the Trinity explosion alone. Many scientists made similar calculations concurrently, though Taylor is often accredited with them. Since then many scientists have also attempted a to calculate a yield through various methods. This paper walks through these methods with a focus on Taylor's method -- based on first principles -- as well as redoing the calculations that he performed with modern tools. In this paper we make use of the state-of-the-art computer vision tools to find a more precise measurement of the blast radius, as well as using curve fitting and numerical integration methods. With more precise measurements we are able to follow in Taylor's footstep towards a more accurate approximation., Comment: 9 pages, 7 figures, submitted to Data Centric Engineering on 08/27/2023 and currently under review

Research of cosmic rays at the Physical Institute of the USSR Academy of Sciences resulted in the construction of the JINR Synchrophasotron. For this purpose the Electrophysical Laboratory of the USSR Academy of Sciences was founded in 1953, which became part of JINR in 1956 as the High Energy Laboratory. The initial milestones to develop experiments at the Laboratory on the Synchrophasotron are presented. Leaders and key participants in the experiments are highlighted, as well as the lessons and results relevant today., Comment: To be published in Proceedings of https://indico.jinr.ru/event/3694/ (PEPAN/EChAYa)

The first modern planetarium was presented in 1923 in Jena, Germany. Very soon in the subsequent years, planetariums were installed in other parts of Europe as well as in America. France, however, got its first planetarium only in 1937, for the World Exhibition organized in Paris. The team that took care of that planetarium was headed by a female amateur astronomer named Reysa Bernson. This choice might seem surprising, but it was not made at random, thanks to her never-ending astronomical activities at that time. This paper aims to bring back memories of this very active amateur astronomer of the 1920s and 1930s, and show the many ways in which astronomy was disseminated a century ago., Comment: published in JAHH, see complements on https://hdl.handle.net/2268/310591

It was proposed that the tensor product structure of the Hilbert space is uniquely determined by the Hamiltonian's spectrum, for most finite-dimensional cases satisfying certain conditions. I show that any such method would lead to infinitely many tensor product structures. The dimension of the space of solutions grows exponentially with the number of qudits. In addition, even if the result were unique, such a Hamiltonian would not entangle subsystems. These results affect the proposals to recover the 3d space from the Hamiltonian., Comment: 3 pages, comments welcome!

In this article, I will explore the nature of interference in translation, especially in technical and scientific texts, using a descriptivist approach. I will have a brief overview of the historical excursion of interference in technical and scientific translation. My aim is to explain this phenomenon and its causes with all its paradoxes, instead of simply condemning it as an example of supposedly bad translation. Thus, I will focus on its status in the bibliography of translation, on the motives for and consequences of interference in specialized translation, as well as on the nature of the arguments given for and against this phenomenon. Therefore the relationship between different societies has always been possible with the act of translation. When civilizations are examined throughout history, it is seen that the dissemination of knowledge among different societies has been achieved by translation. These societies have often become aware of the advancements in technology and science by means of translation. Therefore; translation becomes very significant in technical contact between societies and humans. Since the translation of technical texts is the preliminary scope of this thesis, it will be beneficial to have a brief look at the history of technical translation in the world.

The assumption that the system Hamiltonian for entangled states is additive is widely used in orthodox quantum no-signalling arguments. It is shown that additivity implies a contradiction with the assumption that the system being studied is entangled.

Thomas S. Kuhn interprets the development of the (natural) sciences as a specific dynamical process. Periods of piecemeal growth of knowledge based on widely accepted paradigms are interrupted by bursts of revolutionary changes which lead to new paradigms incommensurate with the earlier ones. This process is briefly illustrated by recalling the changes to classical physics brought about by Einstein's theory of relativity on the one hand, and by quantum theory on the other. Both theories represent fundamental paradigms of contemporary physics. They appear unshakable to the working physicist but according to Kuhn their paradigmatic status is of a temporary nature only. Does Kuhn's framework help us to identify potential future revolutions?, Comment: 8 pages, 3 figures

Einstein presented the Hole Argument against General Covariance, understood as invariance with respect to a change of coordinates, as a consequence of his initial failure to obtain covariant equations that, in the weak static limit, contain Newton's law. Fortunately, about two years later, Einstein returned to General Covariance and found these famous equations of gravity. However, the rejection of his Hole Argument carries a totally different vision of space-time. Its substantivalism notion, which is an essential ingredient in Newtonian theory and also in his special theory of relativity, has to be replaced, following Descartes and Leibniz's relationalism, by a set of "point-coincidences.", Comment: 15 pages. Version accepted for publication in Universe

The scattering of a nucleon beam around a cylinder containing a non-Abelian flux is studied. We confirm all the previsions of Wu and Yang. We consider the generalization to the gauge group $SU(N)$, and derive a classification scheme. Isospin precession is recovered also at the classical limit., Comment: LaTex version of the unpublished preprint BI-TP-82/14, available in inspire (code {Horvathy:1982fx}). 16 pages, no figures

The goal of this article is to give an overview of the current limitations and epistemological barriers in Science and Scientific Philosophy from a very general point of view. We first list and define the types of knowledge nous, doxa and episteme, and the Subject-Observer and Object(s) of study, to proceed showing the different types of barriers that difficult the knowledge of the physical world: limitations in the language, in the logic of the Subject-Observer. Later, we discriminate between technological barriers, (temporary) limits and absolute epistemic barriers. The last type of limits are presented and discussed in some detail: the quantum of action, Planck's scale and quantum gravity (showing the importance of the trans-Planckian scale for structure formation), the cosmological horizon (a limit to the present observable Universe) and the event horizons (disconnecting the inside of some spacetimes from the rest of the Universe). We argue that physical problems in which absolute barriers seem to determine the end of the attainable knowledge, are in fact amenable to be studied, at least indirectly., Comment: 19 pp. 4 figures. Accepted for publication in Cosmos and History

The definition of a quantum system requires a Hilbert space, a way to define the dynamics, and an algebra of observables. The structure of the observable algebra is related to a tensor product decomposition of the Hilbert space and represents the composition of the system by subsystems. It has been remarked that the Hamiltonian may determine this tensor product structure. Here we observe that this fact may lead to questionable consequences in some cases, and does extend to the more general background-independent case, where the Hamiltonian is replaced by a Hamiltonian constraint. These observations reinforces the idea that specifying the observables and the way they interplay with the dynamics, is essential to define a quantum theory. We also reflect on the general role that system decomposition has in the quantum theory., Comment: 14 pages, no figures

This paper is a continuation of a series of works, devoted to various aspects of the 1908 Tunguska event. It is devoted to the Evenki accounts of the 1908 Tunguska event collected in 1920s - 1930s. It is important to research accounts of Evenki who were rather close to the epicenter. The Evenki accounts are important also, because Evenki are natural hunters and pathfinders - their lives depend on their memory and vision. Most of the reviewed in this work accounts were collected at the Evenki conference, when telling a lie was considered to be a serious misconduct. These Evenki accounts are compared with other Tunguska accounts. Also weather conditions associated with the Tunguska event are considered. Some manifestations of the Tunguska event are discussed., Comment: 51 pages, 5 pictures

I present a brief review of the history of the Instituto Argentino de Radioastronom\'ia, a description of its current facilities and projects, and a view of his prospects for the future., Comment: 15 pages, 33 figures, RevMexAA (Serie de Conferencias) 56, 3-17 (2023)

This paper argues that Tycho Brahe's "principal argument against Copernicus" (as the astronomer Christiaan Huygens called it) likely derived from a much older argument regarding the sizes of the "two great lights" described in the first chapter of the book of Genesis. Brahe's argument, that in the Copernican system stars would have to be absurdly large, played an important role in opposition to the Copernican system in the seventeenth century. Brahe presented the argument in an exchange of letters with Christoph Rothmann in 1588-89. Within that exchange Rothmann and Brahe touched both on the question of the two great lights of Genesis and on theologians such as Augustine of Hippo who treated that question. The fundamentals of Brahe's important line of argument against Copernicus thus well pre-dated Copernicus and Brahe., Comment: 11 pages, 3 figures

In commemoration of the fifth anniversary since Nino Boccara's departure, this article offers some personal recollections and provides insight into his life and accomplishments. Detailed bibliography of his works is included together with commentary highlighting his major achievements., Comment: 16 pages, 2 figures with 6 photos

The perturbative treatment of realistic quantum field theories, such as quantum electrodynamics, requires the use of mathematical idealizations in the approximation series for scattering amplitudes. Such mathematical idealisations are necessary to derive empirically relevant models from the theory. Mathematical idealizations can be either controlled or uncontrolled, depending on whether current scientific knowledge can explain whether the effects of the idealization are negligible or not. Drawing upon negative formal results in asymptotic analysis (failure of Borel summability) and renormalization group theory (failure of asymptotic safety), we argue that the mathematical idealizations applied in perturbative quantum electrodynamics should be understood as uncontrolled. This, in turn, leads to the problematic conclusion that such theories do not have theoretical models in the standard understanding of this term. The existence of unquestionable empirically successful theories without theoretical models has significant implications both for our understanding of the theory-model relationship in physics and the concept of empirical adequacy.

What constitutes a scientific discovery? What role do discoveries play in science, its dynamics and social practices? Must every discovery be attributed to an individual discoverer (or a small number of discoverers)? The paper explores these questions by first critically examining extant philosophical explications of scientific discovery $\unicode{x2013}$ the models of scientific discovery, propounded by Kuhn, McArthur, Hudson, and Schindler. As a simple, natural and powerful alternative, we proffer the $\unicode{x201c}$change $\unicode{x2013}$driver model$\unicode{x201d}$: in a nutshell, it takes discoveries to be cognitive scientific results that have epistemically advanced science. The model overcomes the shortcomings of its precursors, whilst preserving their insights. We demonstrate its intensional and extensional superiority, especially with respect to the link between scientific discoveries and the dynamics of science, as well as the award system of science. As an illustration, we apply the considered models of discovery to one of the most momentous discoveries of science: the expansion of the universe. We oppose the 2018 proposal of the International Astronomers$\unicode{x2019}$ Union as too simplistic given the historical complexity of the episode. The change$\unicode{x2013}$ driver model yields a more nuanced and circumspect verdict: (i) The redshift-distance relation should not be named the $\unicode{x201c}$Hubble$\unicode{x2013}$Lema$\unicode{x00EE}$tre Law$\unicode{x201d}$, but $\unicode{x201c}$Slipher-Lundmark-Hubble-Humason Law$\unicode{x201d}$; (ii) Its interpretation in terms of an expanding universe, however, Lema$\unicode{x00EE}$tre ought to be given credit for; but (iii) The establishment of the expansion of the universe, as an evidentially sufficiently warranted result, is a communal achievement, emerging in the 1950s or 1960s.

In this work, we review and extend a version of the old attempt made by Louis de broglie for interpreting quantum mechanics in realistic terms, namely the double solution. In this theory quantum particles are localized waves, i.e, solitons, that are solutions of relativistic nonlinear field equations. The theory that we present here is the natural extension of this old work and relies on a strong time-symmetry requiring the presence of advanced and retarded waves converging on particles. Using this method, we are able to justify wave-particle duality and to explain the violations of Bell's inequalities. Moreover, the theory recovers the predictions of the pilot-wave theory of de Borglie and Bohm, often known as Bohmian mechanics. As a direct consequence, we reinterpret the nonlocal action at a distance presents in the pilot-wave theory. In the double solution developed here there is fundamentally no action at a distance but the theory requires a form of superdeterminism driven by time-symmetry.