This oral history interview provides Yakir Aharonov's perspective on the theoretical discovery of the Aharonov-Bohm effect in 1959, during his PhD studies in Bristol with David Bohm, the reception of the effect, the efforts to test it empirically (up to Tonomura's experiment), and some of the debates regarding the existence of the effect and its interpretation. The interview also discusses related later developments until the 1980s, including modular momentum and Berry's phase. It includes recollections from meetings with Werner Heisenberg, Richard Feynman, and Chen-Ning Yang, also mentioning John Bell, Robert Chambers, Werner Ehrenberg, Sir Charles Frank, Wendell Furry, Gunnar Källén, Maurice Pryce, Nathan Rosen, John Wheeler, and Eugene Wigner.
In social learning environments, agents acquire information from both private signals and the observed actions of predecessors, referred to as history. We define the value of history as the gain in expected payoff from accessing both the private signal and history, compared to relying on the signal alone. We first characterize the information structures that maximize this value, showing that it is highest under a mixture of full information and no information. We then apply these insights to a model of markets for history, where a monopolistic data seller collects and sells access to history. In equilibrium, the seller's dynamic pricing becomes the value of history for each agent. This gives the seller incentives to increase the value of history by designing the information structure. The seller optimal information discloses less information than the socially optimal level.
The history of the Arcetri Institute of Physics at the University of Florence is analyzed from the beginning of the 20th century to the 1960s. Thanks to the arrival of Garbasso in 1913, not only did the Institute gain new premises on Arcetri hill, but also hosted brilliant young physicists such as Rita Brunetti, Enrico Fermi, Franco Rasetti in the '20s and Enrico Persico, Bruno Rossi, Gilberto Bernardini, Daria Bocciarelli, Lorenzo Emo Capodilista, Giuseppe Occhialini and Giulio Racah in the '30s, engaged in the emerging fields of Quantum Mechanics and Cosmic Rays. This internationally renowned Arcetri School dissolved in the late 1930s mainly for the transfer of its protagonists to chairs in other Italian or foreign universities. After the war, the legacy was taken up by some students of this school who formed research groups in the fields of nuclear physics and elementary particle physics. As far as theoretical physics is concerned, after the Fermi and Persico periods, these studies enjoyed a new expansion in the sixties thanks to the arrival of Raoul Gatto who created in Arcetri the first Italian school of theoretical physics.
Hilde ten Berge, Katerina Togka, Xuanqi Pan
et al.
Aim: Lung cancer is the most common cause of cancer death in Portugal. The Dutch–Belgian lung cancer
screening (LCS) study (NELSON), the biggest European LCS study, showed a lung cancer mortality reduction
in a high-risk population when being screened. In this study, the cost–effectiveness of LCS, based on the
NELSON study protocol and outcomes, was evaluated compared with no screening in Portugal. Methods:
The present study modified an established decision tree by incorporating a state-transitionMarkov model
to evaluate the health-related advantages and economic implications of low-dose computed tomography
(LDCT) LCS from the healthcare standpoint in Portugal. The analysis compared screening versus no
screening for a high-risk population aged 50–75 with a smoking history. Various metrics, including clinical
outcomes, costs, quality-adjusted life years (QALYs), life-years (LYs) and the incremental cost–effectiveness
ratio (ICER), were calculated to measure the impact of LDCT LCS. Furthermore, scenario and sensitivity
analyses were executed to assess the robustness of the obtained results. Results: Annual LCS with volumebased
LDCT resulted in €558 million additional costs and 86,678 additional QALYs resulting in an ICER of
€6440 per QALY for one screening group and a lifetime horizon. In total, 13,217 premature lung cancer
deaths could be averted, leading to 1.41 additional QALYs gained per individual diagnosed with lung
cancer. Results are robust based on the sensitivity analyses. Conclusion: This study showed that annual
LDCT LCS for a high-risk population could be cost-effective in Portugal based on a willingness to pay a
threshold of one-time the GDP (€19,290 per QALY gained).
Fourteenth-century Europe was marked by the Renaissance, the large movement of European awakening that started in Italy and encompassed scientific, political, economic, social, and cultural fields. One of the results of this movement was an unprecedented wave of explorations of the lands outside Europe, pioneered by the Portuguese in the fifteenth century. These explorations allowed Portugal to create trading posts and build castles along the West African coasts and establish sugarcane plantations on the Atlantic islands which relied on African slave labor. However, the discovery of the Americas in 1492 dramatically increased the demand for African slaves. This paper traces back the history of the trans-Atlantic slave trade and the atrocities committed against African slaves, and it attempts to highlight the wrongs done to them for centuries in the name of economic progress dictated by the capitalist system.
Résumé
L’Europe du XIVe siècle a été marquée par la Renaissance qui a englobé les domaines scientifique, politique, économique, social et culturel. L’un des résultats de ce mouvement fut une vague d’explorations sans précédent des terres hors d’Europe au XVe siècle, initiée par les Portugais. Ces explorations ont permis au Portugal de créer des postes commerciaux et de construire des forts le long des côtes de l'Afrique de l'Ouest et d'établir des plantations de canne à sucre sur les îles de l'Atlantique qui reposaient sur la main-d'œuvre des esclaves africains. Cependant, la découverte des Amériques en 1492 a considérablement accru la demande d’esclaves africains.Cet article retrace l'histoire de la traite transatlantique des esclaves et des atrocités commises contre les esclaves africains, et tente de mettre en lumière les torts qui leur ont été causés pendant des siècles au nom du progrès économique dicté par le système capitaliste.
Searches for exclusive decays of the Higgs boson into D⁎γ and of the Z boson into D0γ and Ks0γ can probe flavour-violating Higgs boson and Z boson couplings to light quarks. Searches for these decays are performed with a pp collision data sample corresponding to an integrated luminosity of 136.3 fb−1 collected at s=13TeV between 2016–2018 with the ATLAS detector at the CERN Large Hadron Collider. In the D⁎γ and D0γ channels, the observed (expected) 95% confidence-level upper limits on the respective branching fractions are B(H→D⁎γ)<1.0(1.2)×10−3, B(Z→D0γ)<4.0(3.4)×10−6, while the corresponding results in the Ks0γ channel are B(Z→Ks0γ)<3.1(3.0)×10−6.
Emily F. Kerrison, Ron D. Ekers, John Morgan
et al.
Recent observations of interplanetary scintillation (IPS) at radio frequencies have proved to be a powerful tool for probing the solar environment from the ground. But how far back does this tradition really extend? Our survey of the literature to date has revealed a long history of scintillating observations, beginning with the oral traditions of Indigenous peoples from around the globe, encompassing the works of the Ancient Greeks and Renaissance scholars, and continuing right through into modern optics, astronomy and space science. We outline here the major steps that humanity has taken along this journey, using scintillation as a tool for predicting first terrestrial, and then space weather without ever having to leave the ground.
In 1833 William Lardner was a surgeon on the ship Rainha de Portugal stationed off Porto, and in 1834 a surgeon at the Royal Marine Hospital in Lisboa. Lardner wrote two letters to the prestigious British medical journal The Lancet (Lardner, 1833, 1834). He described the onset of cholera, first in Vigo, then in Porto during skirmishes between Liberals and the Miguelistas, then in Aveiro, and eventually in Lisboa (Thomas, 2006). Lardner states that neither Spain nor Portugal had experienced cholera until the London Merchant, sailing from Dover and Falmouth, made port in Vigo in late December 1832. Lardner’s ship, the Rainha, was berthed in Vigo then and proceeded to Porto, arriving on 2 January 1833. Lardner believed that the troops under General Jean-Baptiste Solignac had contracted cholera from persons on the London Merchant and transported the disease to Porto. Cholera progressed down the coast to Aveiro by 3 February 1833 and then to Lisboa in mid-June 1833. Lardner’s letters to The Lancet provide a wealth of information on the progress, diagnosis, and treatment of cholera in Portugal, as well as many scurrilous comments regarding the practice of medicine in Portugal at that time. Elements from his letters and additional context from other sources and how these elements might relate to the Covid-19 pandemic will be explored.
The FC Portugal 3D team is developed upon the structure of our previous Simulation league 2D/3D teams and our standard platform league team. Our research concerning the robot low-level skills is focused on developing behaviors that may be applied on real robots with minimal adaptation using model-based approaches. Our research on high-level soccer coordination methodologies and team playing is mainly focused on the adaptation of previously developed methodologies from our 2D soccer teams to the 3D humanoid environment and on creating new coordination methodologies based on the previously developed ones. The research-oriented development of our team has been pushing it to be one of the most competitive over the years (World champion in 2000 and Coach Champion in 2002, European champion in 2000 and 2001, Coach 2nd place in 2003 and 2004, European champion in Rescue Simulation and Simulation 3D in 2006, World Champion in Simulation 3D in Bremen 2006 and European champion in 2007, 2012, 2013, 2014 and 2015). This paper describes some of the main innovations of our 3D simulation league team during the last years. A new generic framework for reinforcement learning tasks has also been developed. The current research is focused on improving the above-mentioned framework by developing new learning algorithms to optimize low-level skills, such as running and sprinting. We are also trying to increase student contact by providing reinforcement learning assignments to be completed using our new framework, which exposes a simple interface without sharing low-level implementation details.
This review examines complexity science in Heliophysics, describing it not as a discipline, but as a paradigm. In the context of Heliophysics, complexity science is the study of a star, interplanetary environment, magnetosphere, upper and terrestrial atmospheres, and planetary surface as interacting subsystems. Complexity science studies entities in a system (e.g., electrons in an atom, planets in a solar system, individuals in a society) and their interactions, and is the nature of what emerges from these interactions. It is a paradigm that employs systems approaches and is inherently multi- and cross-scale. Heliophysics processes span at least 15 orders of magnitude in space and another 15 in time, and its reaches go well beyond our own solar system and Earth's space environment to touch planetary, exoplanetary, and astrophysical domains. It is an uncommon domain within which to explore complexity science. This review article excavates the lived and living history of complexity science in Heliophysics. It identifies five dimensions of complexity science. It then proceeds in three epochal parts: 1) A pivotal year in the Complexity Heliophysics paradigm: 1996; 2) The transitional years that established foundations of the paradigm (1996-2010); and 3) The emergent literature largely beyond 2010. The history reveals a grand challenge that confronts most physical sciences to understand the research intersection between fundamental science (e.g., complexity science) and applied science (e.g., artificial intelligence and machine learning). A risk science framework is suggested as a way of formulating the challenges in a way that the two converge. The intention is to provide inspiration and guide future research. It will be instructive to Heliophysics researchers, but also to any reader interested in or hoping to advance the frontier of systems and complexity science.
Digital technologies, such as the Internet and Artificial Intelligence, are part of our daily lives, influencing broader aspects of our way of life, as well as the way we interact with the past. Having dramatically changed the ways in which knowledge is produced and consumed, the algorithmic age has also radically changed the relationship that the general public has with History. Fields of History such as Public and Oral History have particularly benefitted from the rise of digital culture. How does our digital culture affect the way we think, study, research and teach the past, as historical evidence spreads rapidly in the public sphere? How do digital technologies promote the study, writing and teaching of History? What should historians, students of history and pre-service history teachers be critically aware of, when swarmed with digitized or born-digital content, constantly growing on the Internet? And while these changes are now visible globally, how is the discipline of History situated within the digital transformation rapidly advancing in Greece? Finally, what are the consequences of these changes for History as a subject taught at Greek secondary schools? These are some of the issues raised in the text that follows, which is part of the course materials of the undergraduate course offered during winter semester 2020-2021 at the School University of Athens, School of Philosophy, Pedagogy, Psychology. Course Title: 'Pedagogics of History: Theory and Practice', Academic Institution: School of Philosophy-Pedagogy-Psychology, University of Athens.
O funcionamento das instituições e as práticas políticas dos agentes do poder, ao longo do século XIX, contribuíram decisivamente para a definição do regime consagrado na Carta Constitucional de 1826 e estabeleceram um intervalo significativo entre a constituição formal e a constituição real. A produção legislativa e as relações estabelecidas entre o Parlamento e o Governo evidenciam esse intervalo e revelam mecanismos de comunicação política informais e fundamentais para a aprovação das propostas legislativas governamentais. Neste artigo procede-se à análise da produção legislativa no período compreendido entre 1851 e 1865 e caracteriza-se o funcionamento interno do Parlamento, bem como o relacionamento deste com o Governo com vista à aprovação das leis. Analisa-se também o fenómeno das ditaduras e a forma com estas se tornaram uma prática política aceite por todos os intervenientes no processo legislativo.
Longitude determination at sea gained increasing commercial importance in the late Middle Ages, spawned by a commensurate increase in long-distance merchant shipping activity. Prior to the successful development of an accurate marine timepiece in the late-eighteenth century, marine navigators relied predominantly on the Moon for their time and longitude determinations. Lunar eclipses had been used for relative position determinations since Antiquity, but their rare occurrences precludes their routine use as reliable way markers. Measuring lunar distances, using the projected positions on the sky of the Moon and bright reference objects--the Sun or one or more bright stars--became the method of choice. It gained in profile and importance through the British Board of Longitude's endorsement in 1765 of the establishment of a Nautical Almanac. Numerous 'projectors' jumped onto the bandwagon, leading to a proliferation of lunar ephemeris tables. Chronometers became both more affordable and more commonplace by the mid-nineteenth century, signaling the beginning of the end for the lunar distance method as a means to determine one's longitude at sea.
Cristiana J. Silva, Carla Cruz, Delfim F. M. Torres
et al.
The COVID-19 pandemic has forced policy makers to decree urgent confinements to stop a rapid and massive contagion. However, after that stage, societies are being forced to find an equilibrium between the need to reduce contagion rates and the need to reopen their economies. The experience hitherto lived has provided data on the evolution of the pandemic, in particular the population dynamics as a result of the public health measures enacted. This allows the formulation of forecasting mathematical models to anticipate the consequences of political decisions. Here we propose a model to do so and apply it to the case of Portugal. With a mathematical deterministic model, described by a system of ordinary differential equations, we fit the real evolution of COVID-19 in this country. After identification of the population readiness to follow social restrictions, by analyzing the social media, we incorporate this effect in a version of the model that allow us to check different scenarios. This is realized by considering a Monte Carlo discrete version of the previous model coupled via a complex network. Then, we apply optimal control theory to maximize the number of people returning to "normal life" and minimizing the number of active infected individuals with minimal economical costs while warranting a low level of hospitalizations. This work allows testing various scenarios of pandemic management (closure of sectors of the economy, partial/total compliance with protection measures by citizens, number of beds in intensive care units, etc.), ensuring the responsiveness of the health system, thus being a public health decision support tool.
In June 1888, Oliver Heaviside received by mail an officially unpublished pamphlet, which was written and printed by the American author Willard J. Gibbs around 1881-1884. This original document is preserved in the Dibner Library of the History of Science and Technology at the Smithsonian Institute in Washington DC. Heaviside studied Gibbs's work very carefully and wrote some annotations in the margins of the booklet. He was a strong defender of Gibbs's work on vector analysis against quaternionists, even if he criticized Gibbs's notation system. The aim of our paper is to analyse Heaviside's annotations and to investigate the role played by the American physicist in the development of Heaviside's work.
O presente artigo analisa a composição das fortunas de imigrantes portugueses em Belém, capital da então província do Grão Pará, entre os anos de 1870 a 1909, caracterizado pela historiografia como o período de boom da economia extrativa da borracha, reconhecida como atrativo aos diferentes grupos de (i) migrantes que se aventuravam para usufruto dos rendimentos por ela alcançados. Fortunas sustentadas sobre novas demandas sociais e econômicas que a borracha haveria de trazer às terras amazônicas, e que evidenciam novas tendências de investimentos, em grande medida, às estruturas modernas do capitalismo, que permaneceram mesmo nos períodos de crise da economia extrativa da borracha, demonstrando a sólida consolidação de novos símbolos de poder e riqueza. O estudo esteia‑se na análise serial de 328 autos cíveis de inventários post mortem e insere‑se num período marcado por um crescimento demográfico acentuado, pela reorganização do espaço urbano de Belém e pelo recrudescimento econômico do mesmo espaço.
Através das constituições sinodais portuguesas medievais, hoje conhecidas e da forma como elas procuravam agir sobre as práticas do clero das respetivas dioceses, procura-se perceber as marcas de um quotidiano próprio, em contexto alargado, que englobava tarefas, usos e procedimentos bem além das funções específicas que competiam ao grupo, e que configuram, afinal, um processo de “aculturação interna” na sociedade em que ele se inseria.