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Theories with no superluminal signaling have greater information-processing power than theories with no superluminal causation
No full textInternational audienceA central goal in the foundations of physics is to understand the structure of physical theories, such as quantum theory, from physical principles. This is often explored by considering various information-theoretic principles. Here, we initiate a similar approach considering relativistic causality principles. No superluminal causation (NSC) and no superluminal signaling (NSS) are distinct relativistic principles, requiring respectively that causal influence/the ability of agents to signal are within the future lightcone. After formalizing their distinction, we investigate how well theories constrained by NSC and NSS perform in a task that involves generating nonclassical correlations. We find a spacetime configuration in which this task cannot be achieved in any theory (classical, quantum, or postquantum) satisfying NSC. However, we show that theories violating NSC but satisfying NSS can perfectly achieve the task. We give a protocol that would, in a world allowing superluminal causation, enable its operational certification without violating NSS, in general spacetimes. In the case of (1 + 1)-dimensional Minkowski spacetime, the task remains achievable in a configuration where measurement outcomes occur arbitrarily earlier in time than the settings, allowing a form of certifiable retrocausality without violating NSS. We illustrate our results by linking two different types of nonclassical postquantum resources: PR boxes and jamming. Our work offers insights into the role of different relativistic causality principles in fundamental physics and paves the way for characterizing the information-theoretic structure of theories obeying such principles
Dalla memoria delle vittime alla storia delle stragi: le commemorazioni come luogo di (ri)elaborazione della storia
No full textInternational audienc
Querelles. Penser par la dispute, au Moyen Âge et aujourd'hui
No full textInternational audienceThis work explores the role of disputes in shaping thought. It approaches the quarrel diachronically, treating it both as an object of analysis in medieval studies and as a methodological tool—that is, one of the ways in which research in medieval studies is constructed.Cet ouvrage interroge le rôle des querelles dans la fabrique de la pensée. Il s’agit de considérer la querelle en diachronie, comme objet d’analyse des études médiévales, et comme outil de la médiévistique, c’est-à-dire l’un des modes de construction de la recherche
La collaboration contre la coopération ? Épreuves de professionnalité et défiance loyale de l’encadrement intermédiaire : le cas de l’école primaire française en contexte néo-gestionnaire
No full textLes recherches sur les limites de la modernisation des services publics se sont surtout attachées à identifier des changements dans la confiance que les usagers pouvaient accorder à ces services. Elles se sont plus rarement penchées sur la confiance des personnels de la fonction publique dans la régulation de leurs propres organisations. C'est ce que nous proposons de faire dans cet article portant sur les effets des transformations en cours de la régulation des écoles primaires françaises sur la confiance des cadres éducatifs à l'égard de leur propre organisation. Pour ce faire, nous exploitons une enquête exploratoire sur trois outils néo-gestionnaires mis en oeuvre récemment dans l'école primaire française : les évaluations d'école, la loi Rilhac de décembre 2021 sur la responsabilité du « pilotage pédagogique » des directeurs d'école et les appels à projets innovants. Reposant sur l'analyse croisée d'entretiens, d'observations et de corpus de documents auprès de directrices d'école et d'inspectrices, il montre que si ces professionnelles sont soumises à des épreuves de professionnalité qui peuvent les fragiliser dans leur fonction, elles demeurent toutefois fortement engagées dans la mise en oeuvre de ces outils et que cette dernière s'accompagne d'une « défiance loyale » pouvant générer un affaiblissement des dynamiques de coopérations durables au profit de collaborations de type instrumental.</div
Byzantine compositions in Renaissance brushstrokes: the survival of maniera greca in Early-Modern pictorial practice
No full textInternational audienceWhat happened to Byzantine art, or maniera greca, during the Italian Renaissance? For Vasari it vanished completely after being replaced with the beautiful “new” art generated by Cimabue, Giotto and Duccio. This fundamental idea, which has been borrowed ever since, still stands as the corner-stone of Early-Modern Art History. It was designed at a time when the Medici wanted to proclaim their city as the art-centre of the world and when Vasari was no less than their court painter. For this reason, Vasari’s ideas do not always reveal the historical realia of his time. Rather, they serve as an ideological discourse showing the triumph of Florentine and Western art over Byzantine tradition. However flattering, this discourse is of course hugely exaggerated. Yes: Renaissance Florence did become a new “cultural Constantinople”. But this did not mean that Byzantine ideas, books and icons went out of trade or fashion. On the contrary, it was precisely Byzantine intellectuals fleeing the Ottomans who brought in Italy the Greek texts that fuelled Renaissance thought and connected once more Western Europe to the ancient Hellenic world. At the same time, the fall of Constantinople in 1453 was accompanied by a massive transfer of artworks from East to the West, where Greek mosaic and tempera icons integrated the prestigious collections of pope Pius II, Lorenzo the Magnificent and cardinal Bessarion. Our communication will show that Renaissance painters were still immensely indebted to these Byzantine models. Consciously or most likely unconsciously, they borrowed Byzantine compositions and visual language, and sometimes developed styles similar to those of contemporary Eastern iconographers. Our inquiry will focus on possible parallels between Early-Modern Italian and Late-Byzantine artworks examining whether their compositions are variations on the same early Christian models, or whether they can considered be considered as an expression of a Pan-European Renaissance “air de temps” – a world of cultural exchange that transcended linguistic, political and theological boundaries
Subdiffusive fractional limit of a jump-renewal equation
No full textIn this paper, we consider an age-structured jump model that arises as a description of continuous time random walks with infinite mean waiting time between jumps. We prove that under a suitable rescaling, this equation converges in the long time large scale limit to a time fractional subdiffusion equation
PaRAMHTRS (Philology And Resolution of Abbreviations in Manuscripts obtained by HTR at Scale)
No full textNational audienc
Sémiotique du mythe
No full textInternational audienceLe mythe peut être appréhendé comme notion et forme discursive en sciences du langage et en sémiotique. Des lectures critiques (1858-2025) de courants variés (pré-saussuriens, structuralistes, etc.) permettent de proposer des cadres théoriques et méthodologiques pour étudier les mythes contemporains
1989 in the East. Between Order and Subversion
No full textApril 15, 2026 by RoutledgeInternational audience1989 in the East revisits the processes that led to the collapse of communist regimes in Central and Eastern Europe, the Balkans and the USSR. This disintegration appeared to be the result of complex mobilisations where the repertoires of action, the institutional and non-institutional ties, the ideological preferences, and the identities of the actors, including the most official ones, have been profoundly changed. The modes of contestation have gone from a self-limited subversion of established institutions, with some forms of collaboration with the regime, to much clearer and more radical forms of head-on opposition. Opposition movements developed according to rhythms and modalities specific to each country, sometimes to each social sphere. Social mobilisations, institutional transformations (both visible and less visible), and the emergence of new actors in all social spheres are therefore central issues in this book.This book, based on rich empirical material, will be of interest to specialists in the region, as well as, more generally, to students of regime change and collapse, political crises, social movements, authoritarian regimes, and the forms of mobilisation that develop within them