1,961 research outputs found

    A p-adic quasi-quadratic point counting algorithm

    Full text link
    In this article we give an algorithm for the computation of the number of rational points on the Jacobian variety of a generic ordinary hyperelliptic curve defined over a finite field of cardinality qq with time complexity O(n2+o(1))O(n^{2+o(1)}) and space complexity O(n2)O(n^2), where n=log⁥(q)n=\log(q). In the latter complexity estimate the genus and the characteristic are assumed as fixed. Our algorithm forms a generalization of both, the AGM algorithm of J.-F. Mestre and the canonical lifting method of T. Satoh. We canonically lift a certain arithmetic invariant of the Jacobian of the hyperelliptic curve in terms of theta constants. The theta null values are computed with respect to a semi-canonical theta structure of level 2Îœp2^\nu p where Îœ>0\nu >0 is an integer and p=\mathrm{char}(\F_q)>2. The results of this paper suggest a global positive answer to the question whether there exists a quasi-quadratic time algorithm for the computation of the number of rational points on a generic ordinary abelian variety defined over a finite field.Comment: 32 page

    Higher dimensional 3-adic CM construction

    Full text link
    We find equations for the higher dimensional analogue of the modular curve X_0(3) using Mumford's algebraic formalism of algebraic theta functions. As a consequence, we derive a method for the construction of genus 2 hyperelliptic curves over small degree number fields whose Jacobian has complex multiplication and good ordinary reduction at the prime 3. We prove the existence of a quasi-quadratic time algorithm for computing a canonical lift in characteristic 3 based on these equations, with a detailed description of our method in genus 1 and 2.Comment: 23 pages; major revie

    Political conflict as moral conflict : multiculturalism and the nation in Germany (2015-2017)

    Full text link
    Cette thĂšse examine, depuis une perspective durkheimienne, le conflit politique en Allemagne sur le multiculturalisme, l’immigration, et l’identitĂ© nationale. L’analyse se fait dans la pĂ©riode entre le dĂ©but de la crise des rĂ©fugiĂ©s en 2015 et l’élection fĂ©dĂ©rale allemande de septembre 2017. J’identifie quatre idĂ©aux moraux, soit des visions idĂ©ales de la communautĂ© allemande qui motivent les acteurs politique : l’idĂ©al des Autonomen qui rejettent tout forme de pouvoir et de domination, l’idĂ©al du Verfassungspatriotismus (le patriotisme constitutionnel) de la SPD (et une partie de la CDU), l’idĂ©al de la nation (ethno)culturelle de la plupart de l’AfD (et la CSU et la WerteUnion), et l’idĂ©al de la nation biologique de l’extrĂȘme droite. Au cƓur de chaque idĂ©al est un objet sacrĂ© qui sert d’autoritĂ© morale qui lĂ©gitimant des prescriptions morales et qui amĂšne Ă  une sĂ©rie de vĂ©ritĂ©s morales et de jugements moraux, la totalitĂ© duquel Émile Durkheim identifie comme un fait moral. Pour les Autonomen et les adhĂ©rents du Verfassungspatriotismus, l’objet sacrĂ© est l’individu conçu Ă  travers le concept de la dignitĂ© humaine. Pour les autres, l’objet sacrĂ© est la nation allemande, conçue en termes (ethno)culturels ou en termes biologiques. Cette thĂšse argumente que ces idĂ©aux moraux sont intrinsĂšquement profanatoires, dans le sens que les prescriptions morales d’un objet sacrĂ© (la dignitĂ© humaine) violent directement l’objet sacrĂ© de l’autre (la nation), et vice-versa. Ces idĂ©aux sont tous en concurrence pour le pouvoir et l’influence, avec comme but d’avoir accĂšs au pouvoir Ă©tatique allemand. Le rĂ©sultat est un conflit politique qui traduit essentiellement un conflit moral. Ces conflits ont lieu dans le domaine lĂ©gal, au sein des partis politique, et Ă  travers la violence politique. Ces conflits touchent un nombre de sujets clĂ©s comme la libertĂ© d’expression, le multiculturalisme, et l’extrĂ©misme politique. La prĂ©sente thĂšse cherche Ă  comprendre ces conflits Ă  travers le prisme du concept durkheimien du fait moral, et dĂ©veloppe une sociologie du conflit moral durkheimien. Cette thĂšse s’inspire Ă©galement de la thĂ©orie de conflit de Randall Collins, qui s’inspire elle aussi de l’Ɠuvre de Durkheim.This dissertation examines, from a Durkheimian perspective, political conflict in Germany around the issues of multiculturalism, immigration, and national identity within the context of the Refugee Crisis beginning in 2015 and ending roughly with the German Federal Election in September 2017. It identifies four moral ideals, or ideal visions of the German community, that motivated political actors during this period: the Autonomen ideal that rejects all forms of power and domination; the ideal of Verfassungspatriotismus (Constitutional Patriotism) of the SPD (and parts of the CDU); the ideal of the cultural or ethnocultural nation of much of the AfD (and the CSU and WerteUnion); and the ideal of the biological nation on the far-right. At the heart of each moral ideal is a sacred object that serves as a moral authority that legitimates certain moral prescriptions, and leads to a set of moral truths and moral judgments, the totality of which Émile Durkheim identifies as a moral fact. For the Autonomen and adherents of Verfassungspatriotismus the sacred object is the individual understood through the concept of human dignity. For others the sacred object is the German nation, understood either in an (ethno)cultural sense or a biological sense. As the dissertation argues, these different moral ideals are inherently profanatory to each other, such that the moral prescriptions inspired by one sacred object (human dignity) directly violate the sacred object of the other (the nation), and vice-versa. These ideals all compete with each other for power and influence within the German political sphere as a means to gain access to (or to dismantle) state power. The result is political conflict that takes place essentially within a moral framework. These conflicts occur in the legal domain, in battles over party leadership and membership, and through political violence; they touch on a number of key issues such as free speech, multiculturalism, and political extremism. This dissertation seeks to understand these conflicts through the prism of Durkheim’s concept of the moral fact and to develop a Durkheimian sociology of moral conflict. In this analysis, the dissertation draws on Randall Collins’ conflict theory, which Durkheim’s work also largely inspires

    Coping with precarisation. Employees' responses to flexiblity and control in Milanese large scale retailing

    Get PDF
    This dissertation deals with retail employees' everyday experiences of precarisation, flexibilisation and labour control. Based on labour process theory and critical psychology, it asks for how workers cope with emerging conflicts, how the construction of both work place consent and conflict capacities passes through workers' own common sense, and how they could increase their disposal over working and living conditions. Empirical analysis relies on qualitative, problem-centred interviews. It points to experiences of forced availability and management's fake participation offers as central, interlinked conflict fields. For all four coping patterns of happy integration, border drawing, personal strike and conflictive negotiation, practices of adaptation and appropriation result as closely connected and reflected in contradictory common sense constructions. Moreover, employees' conflict capacities remain limited due to lacking collective resources and capacities. Enhancing agency potentials in face of precarisation thus requires a reconstruction of collective experiences and strategies as well as a critical analysis of common sense

    A Multifaceted Approach to Promoting Speaking Up Behavior in a Community Hospital

    Get PDF
    Introduction This project describes results of a multifaceted approach to promoting Speaking Up Behavior (SUB) among nurses in a community hospital. Patient safety outcomes, perception of healthy work environment, and nurse retention are connected to caregiver communication. Methods Interventions included development of a structured SUB communication and debriefing tool, SUB administrative policy, leadership rounding and verbal support for SUB, formal recognition of SUB, and SUB education including role-playing activities. Cross-sectional surveys evaluating nurse comfort and confidence with SUB using validated tools were implemented before and after the multifaceted interventions. Results The bedside nurse voluntary turnover rate reduced from 14.5% to 13.0% and the rate of patient safety events with communication as a factor reduced from as high as 2.25 to 0.76 per 1,000 patient days. Nurses had higher levels of comfort speaking up for patient safety and professionalism, as well as higher levels of engagement and trust in speaking up that were statistically significant following the interventions. Implications for Practice Interventions that promote SUB involving organizational culture, policy, leadership, recognition, and education may result in improved outcomes in patient safety, nurse turnover, and likelihood of SUB
    • 

    corecore