16 research outputs found

    One hundred second bit-flip time in a two-photon dissipative oscillator

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    Current implementations of quantum bits (qubits) continue to undergo too many errors to be scaled into useful quantum machines. An emerging strategy is to encode quantum information in the two meta-stable pointer states of an oscillator exchanging pairs of photons with its environment, a mechanism shown to provide stability without inducing decoherence. Adding photons in these states increases their separation, and macroscopic bit-flip times are expected even for a handful of photons, a range suitable to implement a qubit. However, previous experimental realizations have saturated in the millisecond range. In this work, we aim for the maximum bit-flip time we could achieve in a two-photon dissipative oscillator. To this end, we design a Josephson circuit in a regime that circumvents all suspected dynamical instabilities, and employ a minimally invasive fluorescence detection tool, at the cost of a two-photon exchange rate dominated by single-photon loss. We attain bit-flip times of the order of 100 seconds for states pinned by two-photon dissipation and containing about 40 photons. This experiment lays a solid foundation from which the two-photon exchange rate can be gradually increased, thus gaining access to the preparation and measurement of quantum superposition states, and pursuing the route towards a logical qubit with built-in bit-flip protection

    ICTs and the Challenge of Health System Transition in Low and Middle-Income Countries

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    The aim of this paper is to contribute to debates about how governments and other stakeholders can influence the application of ICTs to increase access to safe, effective and affordable treatment of common illnesses, especially by the poor. First, it argues that the health sector is best conceptualized as a ‘knowledge economy’. This supports a broadened view of health service provision that includes formal and informal arrangements for the provision of medical advice and drugs. This is particularly important in countries with a pluralistic health system, with relatively underdeveloped institutional arrangements. It then argues that reframing the health sector as a knowledge economy allows us to circumvent the blind spots associated with donor-driven ICT-interventions and consider more broadly the forces that are driving e-health innovations. It draws on small case studies in Bangladesh and China to illustrate new types of organization and new kinds of relationship between organizations that are emerging. It argues that several factors have impeded the rapid diffusion of ICT innovations at scale including: the limited capacity of innovations to meet health service needs, the time it takes to build new kinds of partnership between public and private actors and participants in the health and communications sectors and the lack of a supportive regulatory environment. It emphasises the need to understand the political economy of the digital health knowledge economy and the new regulatory challenges likely to emerge. It concludes that governments will need to play a more active role to facilitate the diffusion of beneficial ICT innovations at scale and ensure that the overall pattern of health system development meets the needs of the population, including the poor

    Use of anticoagulants and antiplatelet agents in stable outpatients with coronary artery disease and atrial fibrillation. International CLARIFY registry

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    New visions, old practices: policy and regulation in the internet era

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    Raymond Williams’ comment applies as much to the media and communication systems of his time as it does to today’s Internet era. As Silverstone (2007: 26) wrote, “mediated connection and interconnection define the dominant infrastructure for the conduct of social, political and economic life across the globe”. The Internet is no more a neutral configuration of technologies than was the earlier media and communication system. If there are forces that are shaping the Internet’s development in ways that are not equitable then there is a case for countering them. This paper offers an assessment of current trends in policy and regulation that bear on the Internet. The aim is to discern whether visions of a post-neoliberal period are visible in policy and regulatory practice in this area. Though some argue that developments in Internet governance are beginning to wrest control of the Internet away from state or private sector influence, I suggest that this is a very one-sided view. In this paper, I argue that the forces influencing Internet developments are not benign because an unregulated Internet is unlikely to maximise the benefits of the Internet for all. This paper focuses on corporate interests in the Internet’s evolution and on the state’s role in regulating various components of the infrastructure and services that employ the Internet. The following section considers the paradoxical alliance between the neoliberal agenda and the advocates of the open unregulated Internet. The impact of the neoliberal agenda on the telecommunication, broadcast and Internet segments of the media and communication industry is then considered briefly, providing a basis for a more in-depth consideration of the incentives encouraging corporate actors to engage in monopolisation strategies as a means of maximising their profits. In the penultimate section, the likelihood of a shift to policy based on a post-neoliberal paradigm is explored through an examination of some recent developments in network infrastructure, broadcast content and radio frequency spectrum policy

    Copyright infringement online: the case of the Digital Economy Act judicial review in the United Kingdom

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    The proportionality of the UK Digital Economy Act 2010 which aims to curtail illegal peer-to-peer file-sharing is examined in this paper in the light of changes in online norms and culture. Based on an analysis of recent studies and a critical reflection on the nature of changes in digital media production and file-sharing behaviour, we conclude that the Digital Economy Act introduces disproportionate social costs for UK Internet users, with uncertain prospects for improving creative industry revenues. The wider implications of these developments for the emerging online culture are also considered

    Commons/commodity: peer production caught in the Web of the commercial market

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    The development of digital technology and computer networks has enabled many kinds of online collaboration. This article examines Zimuzu, a Chinese case of online peer production that produces and distributes online Chinese subtitles of foreign media content. Zimuzu provides an opportunity to extend our understanding of how the tensions between the commodity and commons production models are being articulated in an online setting. Using empirical evidence collected from face-to-face interviews, online posts and online ethnographic observation, our analysis demonstrates that there is constant negotiation over which aspects of the two seemingly opposing models will be adopted by the community. We argue that it is important to conceptualize the peer production process as being influenced by power relations within and between the translation groups as well as between the groups and other commercial organizations

    Free software production as critical social practice

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    This paper analyses the phenomenon of free and open source software (FOSS) in the light of Luc Boltanski and Ève Chiapello's The new spirit of capitalism. It argues that collaborative FOSS production by volunteer software developers is a species of critical social practice in Boltanski and Chiapello's sense: rooted in resistance to capitalist social relations, and yet also a source of values that justify the new routes to profitability associated with contemporary network capitalism. Advanced via collective projects that are sustained by hacker norms and privately legislated ‘copyleft’ law, the FOSS ethos is apparently antithetical to private property-based accumulation. Yet it can be shown to embody the ‘new spirit of capitalism’ in its most distilled form; moreover FOSS developers have instituted new forms of property and new modes of profit creation around software that are in the process of being adapted for use in other economic sectors. Meanwhile, the private law constraints on profit-seeking that have emerged from the FOSS movement are counteracting some of the social pathologies that accompany network capitalism only to consolidate others. The paper concludes by identifying likely bases for a renewal of critique given these realities

    Exploring the role of commercial stakeholders in open source software evolution

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    It has been lately established that a major success or failure factor of an OSS project is whether or not it involves a commercial company, or more extremely, when a project is managed by a commercial software corporation. As documented recently, the success of the Eclipse project can be largely attributed to IBM’s project management, since the upper part of the developer hierarchy is dominated by its staff. This paper reports on the study of the evolution of three different Open Source (OSS) projects—the Eclipse and jEdit IDEs and the Moodle e-learning system—looking at whether they have benefited from the contribution of commercial companies. With the involvement of commercial companies, it is found that OSS projects achieve sustained productivity, increasing amounts of output produced and intake of new developers. It is also found that individual and commercial contributions show similar stages: developer intake, learning effect, sustained contributions and, finally, abandonment of the project. This preliminary evidence suggests that a major success factor for OSS is the involvement of a commercial company, or more radically, when project management is in hands of a commercial entity

    One hundred second bit-flip time in a two-photon dissipative oscillator

    No full text
    Current implementations of quantum bits (qubits) continue to undergo too many errors to be scaled into useful quantum machines. An emerging strategy is to encode quantum information in the two meta-stable pointer states of an oscillator exchanging pairs of photons with its environment, a mechanism shown to provide stability without inducing decoherence. Adding photons in these states increases their separation, and macroscopic bit-flip times are expected even for a handful of photons, a range suitable to implement a qubit. However, previous experimental realizations have saturated in the millisecond range. In this work, we aim for the maximum bit-flip time we could achieve in a two-photon dissipative oscillator. To this end, we design a Josephson circuit in a regime that circumvents all suspected dynamical instabilities, and employ a minimally invasive fluorescence detection tool, at the cost of a two-photon exchange rate dominated by single-photon loss. We attain bit-flip times of the order of 100 seconds for states pinned by two-photon dissipation and containing about 40 photons. This experiment lays a solid foundation from which the two-photon exchange rate can be gradually increased, thus gaining access to the preparation and measurement of quantum superposition states, and pursuing the route towards a logical qubit with built-in bit-flip protection

    One hundred second bit-flip time in a two-photon dissipative oscillator

    No full text
    Current implementations of quantum bits (qubits) continue to undergo too many errors to be scaled into useful quantum machines. An emerging strategy is to encode quantum information in the two meta-stable pointer states of an oscillator exchanging pairs of photons with its environment, a mechanism shown to provide stability without inducing decoherence. Adding photons in these states increases their separation, and macroscopic bit-flip times are expected even for a handful of photons, a range suitable to implement a qubit. However, previous experimental realizations have saturated in the millisecond range. In this work, we aim for the maximum bit-flip time we could achieve in a two-photon dissipative oscillator. To this end, we design a Josephson circuit in a regime that circumvents all suspected dynamical instabilities, and employ a minimally invasive fluorescence detection tool, at the cost of a two-photon exchange rate dominated by single-photon loss. We attain bit-flip times of the order of 100 seconds for states pinned by two-photon dissipation and containing about 40 photons. This experiment lays a solid foundation from which the two-photon exchange rate can be gradually increased, thus gaining access to the preparation and measurement of quantum superposition states, and pursuing the route towards a logical qubit with built-in bit-flip protection
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