$μ$ Herculis is a bright, nearby quadruple system. Its brightest member, $μ$ Her Aa, displays solar-like oscillations, establishing the system as a crucial benchmark for asteroseismology, provided that its mass can be determined independently of stellar models. We aim to resolve the full hierarchical architecture of the system and determine precise, model-independent dynamical masses for all four components (Aa, Ab, B, and C), along with a consistent astrometric solution for the system's centre of mass. We performed a joint fit of radial velocities, relative astrometry and absolute astrometry from \textit{Hipparcos}, \textit{Gaia} DR3, and ground-based catalogues, spanning nearly three centuries. Our forward-modelling framework simultaneously constrains the Keplerian orbits of the inner Aa--Ab and B--C subsystems, the wide A--BC orbit, and the sky motion and parallax of the total centre of mass. Leveraging several complementary datasets and the decisive 2023 periastron passage of the Aa--Ab pair, we precisely determine all orbital parameters and obtain sub-percent precision on the component masses: $M_{\rm Aa} = 1.134 \pm 0.007\,M_{\odot}$, $M_{\rm Ab} = 0.2286 \pm 0.0006\,M_{\odot
Image segmentation and image recognition are well established computational techniques in the broader discipline of image processing. Segmentation allows to locate areas in an image, while recognition identifies specific objects within an image. These techniques have shown remarkable accuracy with modern images, mainly because the amount of training data is vast. Achieving similar accuracy in digitized images of centuries-old documents is more challenging. This difficulty is due to two main reasons: first, the lack of sufficient training data, and second, because the degree of specialization in a given domain. Despite these limitations, the ability to segment and recognize objects in these collections is important for automating the curation, cataloging, and dissemination of knowledge, making the contents of priceless collections accessible to scholars and the general public. In this paper, we report on our ongoing work in segmenting and labeling images pertaining to shipbuilding treatises from the XVI and XVII centuries, a historical period known as the Age of Exploration. To this end, we leverage SAM2 for image segmentation; Florence2 and ChatGPT for labeling; and a specialized o
This study examines the evolution of references to grain storage structures in medieval European charters, based on a quantitative and semantic analysis of the digitized CEMA (Cartae Europae Medii Aevi) corpus comprising more than 225,000 documents. The author applies text mining and distributional analysis methods to a lexicon of some forty terms designating storage locations (grangia, horreum, granarium, granica, etc.), cross-referencing these data with references to grain and analyzing their semantic contexts over the long term. The analysis reveals a paradigm shift between the early Middle Ages (decentralized, loosely regulated storage) and the 12th-13th centuries (centralization of storage by the ruling classes). Granaries became instruments of spatial polarization and social control, contributing to the accentuation of social domination in medieval Europe. This evolution was accompanied by a new conceptualization of storage, both material and spiritual.
The AAVSO-based historical light curve of the oxygen-rich Mira variable R Leonis is used to determine and analyse the properties of the star's maxima and minima. The pulsation period is found to have shortened by about 3 days over the past two centuries. Superimposed on the mean period are clear modulations on timescales of approximately 35 and 98 years. The depths of extrema show non-random behaviour: minima in particular display strong similarity in depth over extended intervals, with a mean depth difference of 0.26 magnitude for adjacent minima compared to a 0.38 magnitude difference for random pairs. Depth coherence persists for up to about 43 years. Examination of extrema depths over the full observational history of the star reveals gradual long-term changes, consistent with evolution of the circumstellar dust environment.
Historical maps offer an invaluable perspective into territory evolution across past centuries--long before satellite or remote sensing technologies existed. Deep learning methods have shown promising results in segmenting historical maps, but publicly available datasets typically focus on a single map type or period, require extensive and costly annotations, and are not suited for nationwide, long-term analyses. In this paper, we introduce a new dataset of historical maps tailored for analyzing large-scale, long-term land use and land cover evolution with limited annotations. Spanning metropolitan France (548,305 km^2), our dataset contains three map collections from the 18th, 19th, and 20th centuries. We provide both comprehensive modern labels and 22,878 km^2 of manually annotated historical labels for the 18th and 19th century maps. Our dataset illustrates the complexity of the segmentation task, featuring stylistic inconsistencies, interpretive ambiguities, and significant landscape changes (e.g., marshlands disappearing in favor of forests). We assess the difficulty of these challenges by benchmarking three approaches: a fully-supervised model trained with historical labels,
On a centennial timescale, solar activity was quantified based on records of instrumental sunspot observations. This article briefly discusses several aspects of the recent archival investigations of historical sunspot records in the 17th to 18th centuries. This article also reviews the recent updates for the active day fraction and positions of the reported sunspot groups of the Maunder Minimum to show their significance within the observational history. These archival investigations serve as base datasets for reconstructing solar activity.
The total solar irradiance (TSI) varies on timescales of minute to centuries. On short timescales it varies due to the superposition of intensity fluctuations produced by turbulent convection and acoustic oscillations. On longer scale times, it changes due to photospheric magnetic activity, mainly because of the facular brightenings and dimmings caused by sunspots. While modern TSI variations have been monitored from space since 1970s, TSI variations over much longer periods can only be estimated using either historical observations of magnetic features, possibly supported by flux transport models, or from the measurements of the cosmogenic isotope (e.g., \textsuperscript{14}C or \textsuperscript{10}Be) concentrations in tree rings and ice cores. The reconstruction of the TSI in the last few centuries, particularly in the 17th/18th centuries during the Maunder minimum, is of primary importance for studying climatic effects. To separate the temporal components of the irradiance variations, specifically the magnetic cycle from secular variability, we decomposed the signals associated with historical observations of magnetic features and the solar modulation potential $Φ$ by applying
We use natural-language-processing algorithms on a novel dataset of over 900 presidential speeches from ten Latin American countries spanning two centuries to study the dynamics and determinants of presidential policy priorities. We show that most speech content can be characterized by a compact set of policy issues whose relative composition exhibited slow yet substantial shifts over 1819-2022. Presidential attention initially centered on military interventions and the development of state capacity. Attention gradually evolved towards building physical capital through investments in infrastructure and public services and finally turned towards building human capital through investments in education, health, and social safety nets. We characterize the way in which president-level characteristics, like age and gender, predict the main policy issues. Our findings offer novel insights into the dynamics of presidential attention and the factors that shape it, expanding our understanding of political agenda-setting.
By determining which were the most common English words and phrases since the beginning of the 16th century, we obtain a unique large-scale view of the evolution of written text. We find that the most common words and phrases in any given year had a much shorter popularity lifespan in the 16th than they had in the 20th century. By measuring how their usage propagated across the years, we show that for the past two centuries the process has been governed by linear preferential attachment. Along with the steady growth of the English lexicon, this provides an empirical explanation for the ubiquity of the Zipf's law in language statistics and confirms that writing, although undoubtedly an expression of art and skill, is not immune to the same influences of self-organization that are known to regulate processes as diverse as the making of new friends and World Wide Web growth.
DNA traces in the Shroud of Turin reveal a remarkable mixture of human lineages, microbes, plants, animals, and coral accumulated through centuries of handling and travel。 The findings do not prove its age or authenticity, but they expose a hidden biological history preserved in the famous cloth
A detailed bibliography related to physics at the University of Lviv (Leopolis, Lemberg, Lwów) in 18th-19th centuries is presented. Over ninety works of various types are listed with a large share being illustrated by title or starting pages. Brief biographical accounts of the authors are given to put their works in the context of the University history.
This paper discusses the historical evidence for the light jets from the central Super Massive Black Hole of Galaxy in the 4th and 14th centuries. We suggest that the apparitions of a "lightening cross" recorded in 312, 351, 1317 and 1377 years were caused by the line of two jets beamed back-to-back from the center of Milky Way (MW), which is crossing the visible projection of the Galaxy disk. All historical accounts give precise time and geographical locations, where from X-crosses was seen: in the vicinity of Rome, in Jerusalem, in Tver' (the vicinity of Moscow) and in night sky over Moscow, respectively). The positions of the Sun (or the Moon) were also mentioned in the Middle Age manuscripts. These positions coincide with the location of the MW center on the sky map in these specific places and dates, as it is shown with the help of Wolfram Astronomy visualization instruments. We suggest that the gap between jet activity events is about thousand years. The X cross in the sky was mentioned by Plato in {\it Timaeus}\cite{plato}, but he cannot be eyewitness and could only take this from the narratives of older ancient sages. The X cross pictures are multiply stamped on Roman coins
Though pandemic preparedness has been a focus of public health planning for centuries, during which our understanding of infectious disease dynamics has grown, our methodologies for managing outbreaks have remained relatively unchanged. We propose leveraging this history to identify opportunities for actual progress. We contrast current plans with historical outbreak control measures and isolate how the complexities of a modern era yield additional challenges in how best to anticipate and mitigate outbreaks. We analyze a diversity of publicly available modern preparedness plans against the context of a historically-based fictional outbreak control strategy described in Defoe's A Journal of the Plague Year (published 1720). We identify themes in preparedness planning that remain unchanged from historical settings even though they continue to be actively evaluated in planning efforts. More importantly, we isolate critical modern challenges in preparedness planning that remain predominantly unsolved. These modern, unsolved issues offer best avenues for meaningful improvement. Shifting our planning efforts to focus on identified novel issues may greatly strengthen our local- to global-
Here we test Neutral models against the evolution of English word frequency and vocabulary at the population scale, as recorded in annual word frequencies from three centuries of English language books. Against these data, we test both static and dynamic predictions of two neutral models, including the relation between corpus size and vocabulary size, frequency distributions, and turnover within those frequency distributions. Although a commonly used Neutral model fails to replicate all these emergent properties at once, we find that modified two-stage Neutral model does replicate the static and dynamic properties of the corpus data. This two-stage model is meant to represent a relatively small corpus (population) of English books, analogous to a `canon', sampled by an exponentially increasing corpus of books in the wider population of authors. More broadly, this mode -- a smaller neutral model within a larger neutral model -- could represent more broadly those situations where mass attention is focused on a small subset of the cultural variants.
A brief review of the present-day development of cosmology is presented for mixed physical audience. The universe history is briefly described. Unsolved problems are discussed, in particular, the mystery of the cosmological constant and dark energy, the problems of dark matter, and baryogenesis. A brief discussion of the cosmological role of neutrinos is also given.
This article presents twelve records of meteor showers in Arabic chronicles covering period from the 9th to the 19th century. The observations were in Egypt, Morocco, Syria and Yemen. These new addition historical records are considered to be important events which indicate a serious current interest in astronomy.
This review traces the historical trajectory of electricity in agriculture, from the earliest observations of electrical phenomena to the emergence of cold plasmas. Looking back to Antiquity and then to the Enlightenment, it underlines Abbé Bertholon's 18th-century efforts to channel atmospheric electricity to stimulate crops, using devices such as the electro-végétomètre. Although these early electroculture experiments relied on neither quantitative dosimetry nor rigorous methodology, they foreshadowed the idea of a controlled transfer of electrical energy to plants. Then the review examines the historical development of galvanism, electrochemistry, and the physics of gaseous discharges throughout the 19th and 20th centuries, which collectively laid the foundations for contemporary cold-plasma technologies. In the 21st century, plasma agriculture has emerged as an interdisciplinary approach integrating electrical, chemical, radiative, thermal, and fluid-mechanical effects. Applications include seed treatment (preconditioning, seed priming), stimulation of plant growth, soil and water treatment, and decontamination of agri-food products. The review thus reassesses Abbé Bertholon's
During the century of existence of the notion of coherent states, either linear or nonlinear, several schemes for their construction, theoretical or experimental, have been developed. Generally, the mathematical structure of coherent states depends on the choice of ladder operators, and consequently on the structure constants. In this paper, we propose a way to construct generalized coherent states for anharmonic oscillators that is based on a diagonal operator ordering technique (DOOT) applied to generalized hypergeometric functions, that is, on some of the most general special functions. These states are generated by the action of a pair of ladder operators, the creation and the annihilation, whose ordered normal product is equal to the dimensionless Hamiltonian of the quantum system. In addition, the action of these operators is easy to find if the expression for the dimensionless energy eigenvalues is known.
In English literature, the 19th century witnessed a significant transition in styles, themes, and genres. Consequently, the novels from this period display remarkable diversity. This paper explores these variations by examining the evolution of term usage in 19th century English novels through the lens of information retrieval. By applying a query expansion-based approach to a decade-segmented collection of fiction from the British Library, we examine how related terms vary over time. Our analysis employs multiple standard metrics including Kendall's tau, Jaccard similarity, and Jensen-Shannon divergence to assess overlaps and shifts in expanded query term sets. Our results indicate a significant degree of divergence in the related terms across decades as selected by the query expansion technique, suggesting substantial linguistic and conceptual changes throughout the 19th century novels.
Bose-Einstein Condensation is a phenomenon at the heart of many of the past century's most intriguing and fundamental manifestations, such as superfluidity and superconductivity. It was discovered theoretically some 100 years ago, and unequivocally experimentally demonstrated in the context of weakly interacting gases 30 years ago. Since then, it has spawned a revolution in our understanding of fundamental phases of matter and collective quantum dynamics extending across all physical scales and energies, with unforeseen implications and the potential for envisaged quantum technological applications.