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Cultural Production Reveals Transitions to Sustained Human Development in both European and Non-European Societies
No full textSustained human development is often seen as a recent phenomenon, primarily linked to Europe's Industrial Revolution. This perspective has shaped much of our historical understanding, but it relies on a limited set of economic indicators with restricted temporal and geographic coverage. In this article, we introduce Cultural Production as a complementary proxy for human development, particularly suited to long-term and cross-regional comparisons. Cultural production reflects the extent to which societies enable individuals to acquire knowledge, develop skills, and contribute to intellectual and artistic life-conditions closely tied to education, health, material security, and institutional support. We construct a global dataset tracking 122,634 distinct cultural producers (e.g., scientists, artists, writers) and apply ecological methods to estimate the number of unrecorded figures, correcting for differential survivorship bias. The resulting measure enables a broader and deeper reconstruction of human development across time and space. Our results challenge the prevailing view that meaningful development began only in modern Europe. We confirm that Western Europe experienced continuous gains from the 11th century onward, but we also uncover sustained growth in non-Western regions long before the 19th century. Japan shows multiple developmental phases, including a continuous rise after 1500 CE. In China, we trace human development back over 1,500 years, identifying major advances during the Han, Tang, and late imperial periods. In South and West Asia, we reveal marked progress under the Abbasid Caliphate and the Delhi Sultanate. Cultural Production also enables estimates of human development for Antiquity, showing developmental peaks in Classical Greece and Rome, though these were not sustained. Altogether, our findings suggest that all major regions, including non-European societies, transitioned from stagnation to sustained growth well before the Industrial Revolution-some as early as 1000 CE. These results suggest a more widespread and earlier pattern of human development across civilizations than previously recognized
Ordres de charge et de spin dans le modèle t-U-V-J : une approche de particule esclave de spin 1
No full textStrongly-correlated fermion systems on a lattice have been a subject of intense focus in the field of condensed-matter physics. These systems are notoriously difficult to solve, even with state-of-theart numerical methods, especially in regimes of parameters where degrees of freedom compete or cooperate at similar energy and length scales. Here, we introduce a spin-1 slave-particle technique to approximately treat the t-U -V -J fermionic model at arbitrary electron dopings in a simple manner. This formalism relies on a self-consistent cluster mean-field method, and it couples effective pseudo-spin and pseudo-fermion sectors, representing the original electron charge and spin degrees, respectively. We study the phase diagram of the model under various conditions and report the appearance of charge and spin stripes within this formalism. These stripes are a consequence of the cluster mean-field treatment of the pseudo-particle sectors and have not been detected in previous slave-particle studies.Les systèmes de fermions fortement corrélés sur un réseau ont fait l'objet d'une attention particulière dans le domaine de la physique de la matière condensée. Ces systèmes sont réputés difficiles à résoudre, même avec les méthodes numériques les plus avancées, en particulier dans les régimes de paramètres où les degrés de liberté entrent en concurrence ou coopèrent à des échelles d'énergie et de longueur similaires. Nous présentons ici une technique de particule esclave de spin 1 permettant de traiter de manière simple et approximative le modèle fermionique t-U-V-J à des dopages électroniques arbitraires. Ce formalisme repose sur une méthode de champ moyen de cluster auto-cohérente et couple les secteurs pseudo-spin et pseudo-fermion effectifs, représentant respectivement les degrés de charge et de spin électroniques d'origine. Nous étudions le diagramme de phase du modèle dans diverses conditions et signalons l'apparition de bandes de charge et de spin dans ce formalisme. Ces bandes sont une conséquence du traitement par champ moyen sur cluster des secteurs de pseudo-particules et n'ont pas été détectées dans les études précédentes de particules esclaves
Do Your Own Research (?) A Weak Link Between Conspiracism and Preference for First-Hand Evidence in a Perceptual Task
No full textInternational audienceConspiracy theorists often prompt others to “Do your own research.” Could a general desire for such epistemic autonomy—to make up one’s own mind rather than deferring to others’ testimony—explain why some people are attracted to conspiracy theories? In four pre-registered studies (United States and United Kingdom, N = 1196), we test whether participants more likely to believe in conspiracy theories have a stronger preference for forming their own beliefs independently. Participants chose between doing a difficult perceptual task themselves or relying on an expert’s answer. Internal fixed-effect meta-analyses revealed a weak but statistically significant relationship between belief in conspiracy theories and preference for first-hand evidence. By contrast, the relationship between epistemic individualism and this preference was stronger and more robust. This suggests that, although individuals endorsing conspiracy theories express a stronger preference for “doing their own research,” their behavior mostly does not match this preference in non-conspiratorial contexts
The regeneration index, an agronomic tool to scale up agroecology
No full textInternational audienceAgroecology lays on well-established agronomic principles that are universal: endogenous soil fertility, plant nutrition in water and mineral nutrients, and crop protection against plant bio-aggressors, all ensured as much as possible by the biological activity in the cultivated ecosystem. However, their implementation must be adapted to the pedo-climatic and socio-economic contexts of each farm. A variety of tools exist to evaluate a farm's agroecological level and monitor its progression, often with a main objective of pedagogy. In parallel, downstream corporations engaged in the agroecological transition impose on their suppliers' specifications or certification labels often based on means, ill-adapted to the context of farms, and sometimes at odds with the agronomic principles underlying agroecology.To bridge this major gap between agronomic evaluation and economical valorization, and thus allow for a massive scale-up of agroecology in the field, there is a need for a tool that i) relies on a solid agronomic basis and integrates the key principles of agroecology; ii) does not impose means but sets goals that can be achieved in different technical ways; and iii) allows for direct economical valorization in the supply chain.We present here a new agronomic tool that has been developed to meet these three objectives: the Regeneration Index. After presenting the Regeneration Index's co-construction process, the details of its indicators and their scientific foundation, we enlighten with a case study the relevance of the Regeneration Index to reconcile actors of supply chains around a robust agronomic core in complementarity with environmental certifications
Measurement of inclusive dijet cross-sections in proton-proton collisions at TeV with the ATLAS detector
No full textInternational audienceInclusive dijet cross-sections have been measured in proton-proton collisions at a centre-of-mass energy of 13 TeV using data with an integrated luminosity of 140 fb, recorded by the ATLAS detector at the Large Hadron Collider during 2015-2018. Jets are identified using the anti- algorithm with a radius parameter of . The inclusive dijet double-differential cross-sections are measured first as a function of the invariant dijet mass and the half absolute rapidity separation between the two leading jets, , , and second as a function of the invariant dijet mass and the total longitudinal boost of the dijet system, , . The measured dijet system covers the invariant mass range from 240 GeV to almost 10 TeV, with dijet separation and dijet boost . The results are unfolded to the particle level and compared with state-of-the-art next-to-next-to-leading-order full colour perturbative QCD calculations, corrected for non-perturbative and electroweak effects
The Healing Empire: Aromatic Oils, Unguents, and the Reception of Solomon in Byzantium: Aromatic Oils, Unguents, and the Reception of Solomon in Byzantium
No full textInternational audienc
A Cahn--Hilliard--Willmore phase field model for non-oriented interfaces
No full textInternational audienceWe investigate a new phase field model for representing non-oriented interfaces, approximating their area and simulating their area-minimizing flow. Our contribution is related to the approach proposed in arXiv:2105.09627 that involves ad hoc neural networks. We show here that, instead of neural networks, similar results can be obtained using a more standard variational approach that combines a Cahn-Hilliard-type functional involving an appropriate non-smooth potential and a Willmore-type stabilization energy. We show some properties of this phase field model in dimension and, for radially symmetric functions, in arbitrary dimension. We propose a simple numerical scheme to approximate its -gradient flow. We illustrate numerically that the new flow approximates fairly well the mean curvature flow of codimension or interfaces in dimensions and
Aerodynamic consequences of wing damage in dragonfly flapping flight
No full textAccepted in J. Roy. Soc. InterfaceInternational audienceFlapping wings are the primary means by which dragonflies generate forces, but they are susceptible to damage due to their inherent fragility. The damage results in a reduction in wing area and a distortion of the original wing, which in turn leads to a decline in flight ability. Furthermore, the flows of dragonfly fore- and hindwings exhibit an interaction, thus damage to the forewing can also impact the aerodynamic performance of the ipsilateral hindwing. In this study, we examine this problem through CFD (computational fluid dynamics) simulations on a series of damaged dragonfly fore-/hindwing models according to the probability of area loss from the literature. The flow fields and aerodynamic forces for the different damaged wing cases are compared with those for the intact wings. This comparative analysis reveals how the different patterns of wing damage modify the vortex structures around the flapping wings and lead to a drop in aerodynamic force production. The causes behind the diminishing aerodynamic performance are shown to be subtler than the pure area loss and are regulated by the changes in the flow field that result from wing damage. Wing-wing interaction becomes particularly important when forewing damage occurs
Logarithmic Sobolev inequalities: a review on stability and instability results
No full textInternational audienceIn this paper, we review recent results on stability and instability in logarithmic Sobolev inequalities, with a particular emphasis on strong norms. We consider several versions of these inequalities on the Euclidean space, for the Lebesgue and the Gaussian measures, and discuss their differences in terms of moments and stability. We give new and direct proofs, as well as examples and discuss the stability of a logarithmic uncertainty principle. Although we do not cover all aspects of the topic, we hope to contribute to establishing the state of the art
Platform competition and strategic trade-offs for complementors: Heterogeneous reactions to the entry of a new platform
No full textInternational audienceWe study how the entry of a rival platform affects the strategies of the incumbent's complementors. The latter face a trade-off: While the entry threatens their benefits from indirect network effects, it also allows them to escape intense within-platform competition. Studying Epic Games' entry into the PC video game market - until then dominated by Steam - we show that this trade-off does not resolve uniformly, driving heterogeneity in strategic reactions. Complementors with weaker strategic resources (independent developers) were more likely to multihome and became less responsive to the incumbent's attempts to orchestrate collective action through platform-wide sales promotions. In contrast, complementors more reliant on indirect network effects (multiplayer developers) were less likely to multihome and became more responsive to orchestration attempts