8,684 research outputs found

    Looking BK and Moving FD: Toward a Sociocultural Lens on Learning with Programmable Media

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    Part of the Volume on Digital Young, Innovation, and the Unexpected This chapter is a look back at ideas about programming as a form of digital media for learning in the mid-1990s to help realize more of the potential of these tools in the future. It presents a close examination of the work of children who became fluent in programming animations, games, and interactive stories using MicroWorlds Logo. A vignette from the creation of a movie remix by African American girls in a culturally relevant school is analyzed. Their work supports a constructionist perspective that children can learn both programming and other subject-matter ideas through creating personally meaningful projects with programmable media. Unexpected from this view is that the children brought practices from living culturally to define and produce their project and that these cultural practices were integral to their learning. Implications are outlined for educators, policy makers, and researchers to use views of culture in learning with programmable media to connect more children to the benefits of these media

    Towards low-latency real-time detection of gravitational waves from compact binary coalescences in the era of advanced detectors

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    Electromagnetic (EM) follow-up observations of gravitational wave (GW) events will help shed light on the nature of the sources, and more can be learned if the EM follow-ups can start as soon as the GW event becomes observable. In this paper, we propose a computationally efficient time-domain algorithm capable of detecting gravitational waves (GWs) from coalescing binaries of compact objects with nearly zero time delay. In case when the signal is strong enough, our algorithm also has the flexibility to trigger EM observation before the merger. The key to the efficiency of our algorithm arises from the use of chains of so-called Infinite Impulse Response (IIR) filters, which filter time-series data recursively. Computational cost is further reduced by a template interpolation technique that requires filtering to be done only for a much coarser template bank than otherwise required to sufficiently recover optimal signal-to-noise ratio. Towards future detectors with sensitivity extending to lower frequencies, our algorithm's computational cost is shown to increase rather insignificantly compared to the conventional time-domain correlation method. Moreover, at latencies of less than hundreds to thousands of seconds, this method is expected to be computationally more efficient than the straightforward frequency-domain method.Comment: 19 pages, 6 figures, for PR

    Slaying the Leviathan: Critical Jurisprudence and The Treaty of Waitangi

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    This article considers the perspectives of four contributors to the current discourse on the Treaty of Waitangi: Professor Jane Kelsey, Dr Paul McHugh, Professor F M Brookfield and Moana Jackson.  The jurisprudential underpinnings of each authors arguments are examined.  The article focuses on the degree to which two new forms of jurisprudential thought, Critical Legal Studies and Critical Race Theory, have informed the Treaty discourse. The article concludes that, although such critical jurisprudence has yet to permeate New Zealand jurisprudence in any meaningful way, Critical Race Theory could help transform post-settler legal thinking. This article was awarded the Quentin-Baxter LLM prize in Public and International Law in 1997

    Prospects For Detecting Dark Matter With Neutrino Telescopes In Light Of Recent Results From Direct Detection Experiments

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    Direct detection dark matter experiments, lead by the CDMS collaboration, have placed increasingly stronger constraints on the cross sections for elastic scattering of WIMPs on nucleons. These results impact the prospects for the indirect detection of dark matter using neutrino telescopes. With this in mind, we revisit the prospects for detecting neutrinos produced by the annihilation of WIMPs in the Sun. We find that the latest bounds do not seriously limit the models most accessible to next generation kilometer-scale neutrino telescopes such as IceCube. This is largely due to the fact that models with significant spin-dependent couplings to protons are the least constrained and, at the same time, the most promising because of the efficient capture of WIMPs in the Sun. We identify models where dark matter particles are beyond the reach of any planned direct detection experiments while within reach of neutrino telescopes. In summary, we find that, even when contemplating recent direct detection results, neutrino telescopes still have the opportunity to play an important as well as complementary role in the search for particle dark matter.Comment: 13 pages, 6 figure

    Dark Matter and Collider Phenomenology with two light Supersymmetric Higgs Bosons

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    Recently, it has been pointed out that two different excesses of events observed at LEP could be interpreted as the CP-even Higgs bosons of the MSSM with masses of approximately 98 and 114 GeV. If this is the case, the entire MSSM Higgs sector is required to be light. In this article, we explore such a scenario in detail. We constrain the Higgs and supersymmetric spectrum using BB physics constraints as well as the magnetic moment of the muon. We then point out the implications for neutralino dark matter -- next generation direct detection experiments will be sensitive to all MSSM models with such a Higgs sector. Finally, we find that all models outside of a very narrow corridor of the parameter space have a charged Higgs boson which will be observed at the LHC. In those exceptional models which do not contain an observable charged Higgs, a light top squark will always be seen at the LHC, and likely at the Tevatron.Comment: 12 pages, 18 figure

    Distinguishing Supersymmetry From Universal Extra Dimensions or Little Higgs Models With Dark Matter Experiments

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    There are compelling reasons to think that new physics will appear at or below the TeV-scale. It is not known what form this new physics will take, however. Although The Large Hadron collider is very likely to discover new particles associated with the TeV-scale, it may be difficult for it to determine the nature of those particles, whether superpartners, Kaluza-Klein modes or other states. In this article, we consider how direct and indirect dark matter detection experiments may provide information complementary to hadron colliders, which can be used to discriminate between supersymmetry, models with universal extra dimensions, and Little Higgs theories. We find that, in many scenarios, dark matter experiments can be effectively used to distinguish between these possibilities.Comment: 23 pages, 7 figures, references added in version

    Inelastic Dark Matter As An Efficient Fuel For Compact Stars

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    Dark matter in the form of weakly interacting massive particles is predicted to become gravitationally captured and accumulate in stars. While the subsequent annihilations of such particles lead to the injection of energy into stellar cores, elastically scattering dark matter particles do not generally yield enough energy to observably impact stellar phenomenology. Dark matter particles which scatter inelastically with nuclei (such that they reconcile the annual modulation reported by DAMA with the null results of CDMS and other experiments), however, can be captured by and annihilate in compact stars at a much higher rate. As a result, old white dwarf stars residing in high dark matter density environments can be prevented from cooling below several thousand degrees Kelvin. Observations of old, cool white dwarfs in dwarf spheroidal galaxies, or in the inner kiloparsec of the Milky Way, can thus potentially provide a valuable test of the inelastic dark matter hypothesis.Comment: 6 pages, 2 figur
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