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The experiment performed by Henry Cavendish to measure the density of the earth, is in numerous textbooks described as a measurement of the universal gravitational constant, G, even if we know that this was not true. In this paper, a study on how common this "myth" is based on the checklist developed by Leite on a total of 84 textbooks. The prevalence of the myth in most textbooks throughout the 20th century indicates a focus on the contemporary interests of authors and the physics community in presenting the development of physics. An explanation of the prevalence of the myth and a different approach
"Rigor" is an often sought after but ill-defined concept in education. This work reviews several models of rigor from current literature before proposing a tool which is used to analyze science education throughout history. The 20\textsuperscript{th} century science education in the United States was subject to changing sociopolitical motivations about the use of science both in general and for students. These factors as well as developments in theory of learning and broad education reforms had changing affects on the level of rigor in science education. This work analyzes the theoretical level of rigor of science education in the US based on two main motivating factors for science education; science as a social endeavor and science as a discipline, throughout the 20\textsuperscript{th} century.
The first half of the 20th century in the history of Russian mathematics is striking with a combination of dramaticism, sometimes a tragedy, and outstanding achievements. The paper is devoted to St. Petersburg-Leningrad Mathematical School. It is based on a chapter in the multi-author monograph "Mathematical Petersburg. History, science, sights" (SPb: Educational projects, 2018, 336 pp. in Russian).
Classifier-free guidance (CFG) is a key technique for improving conditional generation in diffusion models, enabling more accurate control while enhancing sample quality. It is natural to extend this technique to video diffusion, which generates video conditioned on a variable number of context frames, collectively referred to as history. However, we find two key challenges to guiding with variable-length history: architectures that only support fixed-size conditioning, and the empirical observation that CFG-style history dropout performs poorly. To address this, we propose the Diffusion Forcing Transformer (DFoT), a video diffusion architecture and theoretically grounded training objective that jointly enable conditioning on a flexible number of history frames. We then introduce History Guidance, a family of guidance methods uniquely enabled by DFoT. We show that its simplest form, vanilla history guidance, already significantly improves video generation quality and temporal consistency. A more advanced method, history guidance across time and frequency further enhances motion dynamics, enables compositional generalization to out-of-distribution history, and can stably roll out ex
This preliminary paper presents an interactive Evidence-RAG workspace for editorial assessment of AI-assisted peer review in the Journal of Digital History. The workflow makes model recommendations easier to inspect by linking reviewer comments, paper evidence, retrieval traces, and reproducibility checks. The system does not replace editors or reviewers. It treats large language models as auditable assistants whose outputs must be checked by human scholars. We describe the current pipeline: paper conversion, semantic chunking, vector indexing, retrieval-augmented evidence assessment, and a lightweight editorial interface. This is a preliminary version of a full paper associated with the accepted presentation "Towards an Interactive Evidence-RAG Peer-Review Workspace for the Journal of Digital History" at the conference AI through History, History through AI, C2DH, University of Luxembourg, 15-16 June 2026. The work was submitted to the conference on 26 February 2026. We also report a first editor-annotation analysis of 80 saved decisions for the Claude-Qwen audit configuration. For Claude-Qwen, strict editor-confirmed accuracy is 70.0%, the correct-or-mostly-correct rate is 86.2%.
Camera-controlled video generation has made substantial progress, enabling generated videos to follow prescribed viewpoint trajectories. However, existing methods usually learn camera-specific conditioning through camera encoders, control branches, or attention and positional-encoding modifications, which often require post-training on large-scale camera-annotated videos. Training-free alternatives avoid such post-training, but often shift the cost to test-time optimization or extra denoising-time guidance. We propose Warp-as-History, a simple interface that turns camera-induced warps into camera-warped pseudo-history with target-frame positional alignment and visible-token selection. Given a target camera trajectory, we construct camera-warped pseudo-history from past observations and feed it through the model's visual-history pathway. Crucially, we align its positional encoding with the target frames being denoised and remove warped-history tokens without valid source observations. Without any training, architectural modification, or test-time optimization, this interface reveals a non-trivial zero-shot capability of a frozen video generation model to follow camera trajectories.
The topic is the history of the concepts of equivalence relation, Cauchy sequence, and metric space. The thesis is that disused definitions of these notions could profitably be revived.
Infinitesimals have seen ups and downs in their tumultuous history. In the 18th century, d'Alembert set the tone by describing infinitesimals as chimeras. Some adversaries of infinitesimals, including Moigno and Connes, picked up on the term. We highlight the work of Cauchy, Noël, Poisson and Riemann. We also chronicle reactions by Moigno, Lamarle and Cantor, and signal the start of a revival with Peano.
British biophysics has a tradition of scientific invention and innovation, resulting in new technologies transforming biological insight, such as rapid DNA sequencing, super-resolution and label-free microscopy, high-throughput and single-molecule bio-sensing, and bio-inspired synthetic materials. Some advances were established through democratised platforms and many have biomedical success, a key example involving the SARS-CoV-2 spike protein during the COVID-19 pandemic. Here, three UK labs made crucial contributions revealing how the spike protein targets human cells, and how therapies of vaccines and neutralizing nanobodies work, enabled largely through biophysical innovations of cryo-electron microscopy. Here, we discuss leading-edge innovations which resulted from discovery-led British 'Physics of Life' research (capturing blends of physical-life sciences research in the UK including biophysics and biological physics) and have matured into wide-reaching sustainable commercial ventures enabling translational impact. We describe the biophysical science which led to these academic spinouts, presenting the scientific questions that were addressed through innovating new techniques
A brief but complete historical survey of the theory of equilibrium figures from its early origins, dating back to 17th-century, until the latest 20th-century developments, with a view towards its applications, is carried out.
Based on palaeoenvironmental, historical and archaeological data, the paper proposes possible climatic impacts on the history of the Avar Khaganate, which comprised the Carpathian Basin between the late 6th and the early 9th century AD. While the establishment of the Avars in East Central Europe took place within a period characterised by cold and dry climatic conditions (recently identified as Late Antique Little Ice Age), more stable climatic parameters may have favoured the stabilisation of Avar rule after a crisis in the aftermath of 626 AD. Data indicates growth of settlement and agricultural activity up to the mid-8th century. These developments did not necessarily strengthen central power, but may have contributed to a greater autonomy of various groups on the basis of increased resources. The Khaganate quickly disintegrated faced by the Carolingian advance of the 790s; the last decades of documented Avar presence were again accompanied by environmental vicissitudes.
A formalism is proposed to describe entangled quantum histories, and their entanglement entropy. We define a history vector, living in a tensor space with basis elements corresponding to the allowed histories, i.e. histories with nonvanishing amplitudes. The amplitudes are the components of the history vector, and contain the dynamical information. Probabilities of measurement sequences, and resulting collapse, are given by generalized Born rules: they are all expressed by means of projections and scalar products involving the history vector. Entangled history states are introduced, and a history density matrix is defined in terms of ensembles of history vectors. The corresponding history entropies (and history entanglement entropies for composite systems) are explicitly computed in two examples taken from quantum computation circuits.
Space Very Long Baseline Interferometry is a radio astronomy technique distinguished by a record-high angular resolution reaching single-digit microseconds of arc. The paper provides a brief account of the history of developments of this technique over the period 1960s-2020s.
Mathematical concepts and results have often been given a long history, stretching far back in time. Yet recent work in the history of mathematics has tended to focus on local topics, over a short term-scale, and on the study of ephemeral configurations of mathematicians, theorems or practices. The first part of the paper explains why this change has taken place: a renewed interest in the connections between mathematics and society, an increased attention to the variety of components and aspects of mathematical work, and a critical outlook on historiography itself. The problems of a long-term history are illustrated and tested using a number of episodes in the nineteenth-century history of Hermitian forms, and finally, some open questions are proposed.
Not only motivated by the fact that the publication of the GAFT first appeared 60 years ago in print we reconstruct its history and so show that it is no exaggeration to claim that it has appeared already 75 years ago!
The formulation of a measurement theory for relativistic quantum field theory (QFT) has recently been an active area of research. In contrast to the asymptotic measurement framework that was enshrined in QED, the new proposals aim to supply a measurement framework for measurements in local spacetime regions. This paper surveys episodes in the history of quantum theory that contemporary researchers have identified as precursors to their own work and discusses how they laid the groundwork for current approaches to local measurement theory for QFT.
It is convenient to describe a quantum system at all times by means of a "history operator" $C$, encoding measurements and unitary time evolution between measurements. These operators naturally arise when computing the probability of measurement sequences, and generalize the "sum over position histories " of the Feynman path-integral. As we argue in the present note, this description has some computational advantages over the usual state vector description, and may help to clarify some issues regarding nonlocality of quantum correlations and collapse. A measurement on a system described by $C$ modifies the history operator, $C \rightarrow PC$, where $P$ is the projector corresponding to the measurement. We refer to this modification as "history operator collapse". Thus $C$ keeps track of the succession of measurements on a system, and contains all histories compatible with the results of these measurements. The collapse modifies the history content of $C$, and therefore modifies also the past (relative to the measurement), but never in a way to violate causality. Probabilities of outcomes are obtained as $Tr(C^\dagger P C)/Tr(C^\dagger C)$. A similar formula yields probabilities fo
This paper gives a short review of the history of statistical physics starting from D. Bernoulli's kinetic theory of gases in the 18th century until the recent new developments in nonequilibrium kinetic theory in the last decades of this century. The most important contributions of the great physicists Clausius, Maxwell and Boltzmann are sketched. It is shown how the reversibility and the recurrence paradox are resolved within Boltzmann's statistical interpretation of the second law of thermodynamics. An approach to classical and quantum statistical mechanics is outlined. Finally the progress in nonequilibrium kinetic theory in the second half of this century is sketched starting from the work of N.N. Bogolyubov in 1946 up to the progress made recently in understanding the diffusion processes in dense fluids using computer simulations and analytical methods.
We present in this chapter (Chapter II) the history of ideas which lead up to the development of modern knot theory. We are more detailed when pre-XX century history is reported. With more recent times we are more selective, stressing developments related to Jones type invariants of links. In the Appendix, A.Przybyszewska translation of Preface to P.Heegaard Dissertation (1898) is given.
John Clark was inventor of the Eureka machine to generate hexameter Latin verse. He labored for 13 years from 1832 to implement the device that could compose at random over 26 million different lines of well-formed verse. This paper proposes that Clark should be regarded as an early cognitive scientist. Clark described his machine as an illustration of a theory of "kaleidoscopic evolution" whereby the Latin verse is "conceived in the mind of the machine" then mechanically produced and displayed. We describe the background to automated generation of verse, the design and mechanics of Eureka, its reception in London in 1845 and its place in the history of language generation by machine. The article interprets Clark's theory of kaleidoscopic evolution in terms of modern cognitive science. It suggests that Clark has not been given the recognition he deserves as a pioneer of computational creativity.