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Le Groupe Interdisciplinaire sur l'Électricité Atmosphérique Naturelle (GIEAN) : Retour sur une expérience interdisciplinaire radicale
No full textThis article analyses interdisciplinarity as it was practiced or created conflicts within the realm of a collective project, the GIEAN (Groupe Interdisciplinaire sur l’Électricité Atmosphérique Naturelle), which brought together a panel of researchers from different disciplines to identify obstacles on the one hand, and heuristic and epistemological contributions on the other hand. The meetings and exchanges provided most of the material analyzed by the two authors, who were also participant-observers of the project. This article provides a threefold analysis: that of the genesis of the project, of the first meetings and the institutional formalization; that of the objects of study, their construction by the different disciplines, which revealed different research timeframes, but also the implicit — or sometimes explicit — unconsidered hierarchies of the disciplines, revealing different but not entirely opposed regimes of truth and scientific proof. The third analysis finally questions the multiple effects of interdisciplinarity on the project, the disciplines, and the researchers, but also the research structure that supported and accompanied the project — in this case the “Maison des Sciences de l’Homme (MSH)” — to lead to, in the form of an epilogue, the manner in which this article was received by the co-sponsor of the project. From start to finish, this paper presents a writing style centered on interdisciplinary encounters and practices, because if the results of funded research projects are those most often published, the approaches, obstacles, implicit prejudices, and epistemological contributions — in short, everything that forms the record and infra-narrative of a project — are rarely questioned and capitalized on. But is not the discipline of science also about knowing how to communicate by questioning what is communicated?Cet article vise à analyser l’interdisciplinarité telle qu’elle a été mise en pratique ou en tension sur le terrain d’un projet collectif, le GIEAN (Groupe Interdisciplinaire sur l’Électricité Atmosphérique Naturelle), ayant réuni un panel de chercheurs de disciplines différentes pour identifier d’une part les facteurs de blocages, et d’autre part les apports heuristiques et épistémologiques. Les moments de rencontres et d’échanges fournissent la plus grande partie du matériau analysé par les deux auteurs, également participants-observateurs du projet. L’article propose une triple lecture : celle de la genèse du projet, des premières rencontres et de sa formalisation institutionnelle, celle ensuite des objets d’étude, de leurs constructions par les différentes disciplines à travers lesquelles se manifestent des temporalités de recherche différentes, mais aussi des impensés implicites — ou parfois explicites — de hiérarchisation des disciplines, révélant des régimes de vérité et d’administration de la preuve scientifique différents sans être entièrement opposés. Une troisième lecture interroge enfin les effets pluriels de l’interdisciplinarité sur le projet, les disciplines, les chercheurs, mais aussi la structure de recherche qui a soutenu et accompagné le projet — en l’occurrence une Maison des Sciences de l’Homme (MSH) —, pour conduire, sous forme d’épilogue, à la manière dont a été reçu cet article par la co-porteuse du projet. De bout en bout, ce papier propose donc une écriture centrée sur les rencontres et pratiques interdisciplinaires, car si les résultats d’un projet de recherche financé sont le plus souvent publiés, les démarches, les blocages, les préjugés implicites et les apports épistémologiques — bref, tout ce qui forme la mémoire et l’infra-récit d’un projet — sont quant à eux rarement interrogés et capitalisés. Or faire de la science, n’est-ce pas aussi savoir transmettre en s’interrogeant sur ce qui est transmis
Transport maritime de marchandises : la construction d’un système juridique complexe dépassant le mythe de l’uniformité
No full textAs the international transport of goods by sea involves various kinds of international trade operators, uniformity of the law appears to be the best way to satisfy the security requirements of these various operators. Nevertheless, individual States cannot create new rules for this activity, by simply unifying regulations in a conventional manner. There is a conflict between the desire for uniformity and the realities of implementing rules, as a consequence of divergences within the convention. This is the reason for which maritime actors have tried to standardize contracts, and support ruling jurisdictions. How can such practices contribute to the uniformity of soft law?Dans la mesure où le transport maritime de marchandises implique divers types d'opérateurs commerciaux internationaux, l'uniformité de la règlementation applicable semble être le meilleur moyen de satisfaire aux exigences de sécurité de ces différents acteurs. Il est donc nécessaire de se demander si cet idéal d’uniformisation du droit du transport maritime de marchandises tenté par les États est atteignable voire même souhaitable ou s’il ne faut pas constater en la matière que les opérateurs du transport international maritime de marchandises, loin d’être pénalisés par le conflit de normes applicables, n’y trouvent pas la souplesse nécessaire pour adapter le cadre juridique à leur propre contrat de transport
Resynchronized Uniformization and Definability Problems for Rational Relations
No full textRegular synchronization languages can be used to define rational relations offinite words, and to characterize subclasses of rational relations, likeautomatic or recognizable relations. We provide a systematic study of thedecidability of uniformization and definability problems for subclasses ofrational relations defined in terms of such synchronization languages. Werephrase known results in this setting and complete the picture by addingseveral new decidability and undecidability results
Maker-Breaker domination game on trees when Staller wins
No full textIn the Maker-Breaker domination game played on a graph , Dominator's goalis to select a dominating set and Staller's goal is to claim a closedneighborhood of some vertex. We study the cases when Staller can win the game.If Dominator (resp., Staller) starts the game, then (resp., ) denotes the minimum number of moves Stallerneeds to win. For every positive integer , trees with \gamma_{\rmSMB}'(T)=k are characterized and a general upper bound on is proved. Let be the subdivided star obtained fromthe star with edges by subdividing its edges times, respectively. Then is determined in all the casesexcept when and each is even. The simplest formula isobtained when there are at least two odd s. If and are the twosmallest such numbers, then . For caterpillars, exact formulas for \gamma_{\rmSMB} and for are established
Conditional Dichotomy of Boolean Ordered Promise CSPs
No full textPromise Constraint Satisfaction Problems (PCSPs) are a generalization ofConstraint Satisfaction Problems (CSPs) where each predicate has a strong and aweak form and given a CSP instance, the objective is to distinguish if thestrong form can be satisfied vs. even the weak form cannot be satisfied. Sincetheir formal introduction by Austrin, Guruswami, and H\aa stad, there has beena flurry of works on PCSPs [BBKO19,KO19,WZ20]. The key tool in studying PCSPsis the algebraic framework developed in the context of CSPs where the closureproperties of the satisfying solutions known as the polymorphisms are analyzed. The polymorphisms of PCSPs are much richer than CSPs. In the Boolean case, westill do not know if dichotomy for PCSPs exists analogous to Schaefer'sdichotomy result for CSPs. In this paper, we study a special case of BooleanPCSPs, namely Boolean Ordered PCSPs where the Boolean PCSPs have the predicate. In the algebraic framework, this is the special case of BooleanPCSPs when the polymorphisms are monotone functions. We prove that BooleanOrdered PCSPs exhibit a computational dichotomy assuming the Rich 2-to-1Conjecture [BKM21] which is a perfect completeness surrogate of the UniqueGames Conjecture. Assuming the Rich 2-to-1 Conjecture, we prove that a Boolean Ordered PCSP canbe solved in polynomial time if for every , it has polymorphismswhere each coordinate has Shapley value at most , else it is NP-hard.The algorithmic part of our dichotomy is based on a structural lemma thatBoolean monotone functions with each coordinate having low Shapley value havearbitrarily large threshold functions as minors. The hardness part proceeds byshowing that the Shapley value is consistent under a uniformly random 2-to-1minor. Of independent interest, we show that the Shapley value can beinconsistent under an adversarial 2-to-1 minor.Comment: 20 pages, 1 figur
Supermanifolds corresponding to the trivial vector bundle over torus
No full textAll supermanifolds whose retract is determined by the trivial bundle of rank over the torus are -homogeneous if and only if is homogeneous
Testing Distributions of Huge Objects
No full textWe initiate a study of a new model of property testing that is a hybrid oftesting properties of distributions and testing properties of strings.Specifically, the new model refers to testing properties of distributions, butthese are distributions over huge objects (i.e., very long strings).Accordingly, the model accounts for the total number of local probes into theseobjects (resp., queries to the strings) as well as for the distance betweenobjects (resp., strings), and the distance between distributions is defined asthe earth mover's distance with respect to the relative Hamming distancebetween strings. We study the query complexity of testing in this new model, focusing on threedirections. First, we try to relate the query complexity of testing propertiesin the new model to the sample complexity of testing these properties in thestandard distribution testing model. Second, we consider the complexity oftesting properties that arise naturally in the new model (e.g., distributionsthat capture random variations of fixed strings). Third, we consider thecomplexity of testing properties that were extensively studied in the standarddistribution testing model: Two such cases are uniform distributions and pairsof identical distributions
The syntactic side of autonomous categories enriched over generalised metric spaces
No full textPrograms with a continuous state space or that interact with physicalprocesses often require notions of equivalence going beyond the standard binarysetting in which equivalence either holds or does not hold. In this paper weexplore the idea of equivalence taking values in a quantale V, which covers thecases of (in)equations and (ultra)metric equations among others. Our mainresult is the introduction of a V-equational deductive system for linear{\lambda}-calculus together with a proof that it is sound and complete. In factwe go further than this, by showing that linear {\lambda}-theories based onthis V-equational system form a category that is equivalent to a category ofautonomous categories enriched over 'generalised metric spaces'. If weinstantiate this result to inequations, we get an equivalence with autonomouscategories enriched over partial orders. In the case of (ultra)metricequations, we get an equivalence with autonomous categories enriched over(ultra)metric spaces. We additionally show that this syntax-semanticscorrespondence extends to the affine setting. We use our results to developexamples of inequational and metric equational systems for higher-orderprogramming in the setting of real-time, probabilistic, and quantum computing.Comment: Journal version of "An Internal Language for Categories Enriched over Generalised Metric Spaces" [arXiv:2105.08473] (https://doi.org/10.4230/LIPIcs.CSL.2022.16
Space-Fluid Adaptive Sampling by Self-Organisation
No full textA recurrent task in coordinated systems is managing (estimating, predicting,or controlling) signals that vary in space, such as distributed sensed data orcomputation outcomes. Especially in large-scale settings, the problem can beaddressed through decentralised and situated computing systems: nodes canlocally sense, process, and act upon signals, and coordinate with neighbours toimplement collective strategies. Accordingly, in this work we devisedistributed coordination strategies for the estimation of a spatial phenomenonthrough collaborative adaptive sampling. Our design is based on the idea ofdynamically partitioning space into regions that compete and grow/shrink toprovide accurate aggregate sampling. Such regions hence define a sort ofvirtualised space that is "fluid", since its structure adapts in response topressure forces exerted by the underlying phenomenon. We provide an adaptivesampling algorithm in the field-based coordination framework, and prove it isself-stabilising and locally optimal. Finally, we verify by simulation that theproposed algorithm effectively carries out a spatially adaptive sampling whilemaintaining a tuneable trade-off between accuracy and efficiency
Simulation by Rounds of Letter-to-Letter Transducers
No full textLetter-to-letter transducers are a standard formalism for modeling reactivesystems. Often, two transducers that model similar systems differ locally fromone another, by behaving similarly, up to permutations of the input and outputletters within "rounds". In this work, we introduce and study notions ofsimulation by rounds and equivalence by rounds of transducers. In our setting,words are partitioned to consecutive subwords of a fixed length , calledrounds. Then, a transducer is -round simulated by transducer if, intuitively, for every input word , we can permute theletters within each round in , such that the output of onthe permuted word is itself a permutation of the output of on. Finally, two transducers are -round equivalent if they simulate eachother. We solve two main decision problems, namely whether -roundsimulates (1) when is given as input, and (2) for anexistentially quantified . We demonstrate the usefulness of the definitions by applying them to processsymmetry: a setting in which a permutation in the identities of processes in amulti-process system naturally gives rise to two transducers, whose -roundequivalence corresponds to stability against such permutations