Entropy inequalities and Bell inequalities for two-qubit systems

Sufficient conditions for (the non-violation of) the Bell-CHSH inequalities in a mixed state of a two-qubit system are: 1) The linear entropy of the state is not smaller than 0.5, 2) The sum of the conditional linear entropies is non-negative, 3) The von Neumann entropy is not smaller than 0.833, 4) The sum of the conditional von Neumann entropies is not smaller than 0.280.Comment: Errors corrected. See L. Jakobcyk, quant-ph/040908

Model theory for modal logic—Part III existence and predication

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43175/1/10992_2004_Article_BF00293421.pd

Analog Computer Research

Contains reports on two research projects

Developing sexual competence? Exploring strategies for the provision of effective sexualities and relationships education

School-based sexualities and relationships education (SRE) offers one of the most promising means of improving young people's sexual health through developing 'sexual competence'. In the absence of evidence on whether the term holds the same meanings for young people and adults (e.g. teachers, researchers, policy-makers), the paper explores 'adult' notions of sexual competence as construed in research data and alluded to in UK Government guidance on SRE, then draws on empirical research with young people on factors that affect the contexts, motivations and outcomes of sexual encounters, and therefore have implications for sexual competence. These data from young people also challenge more traditional approaches to sexualities education in highlighting disjunctions between the content of school-based input and their reported sexual experience. The paper concludes by considering the implications of these insights for developing a shared notion of what SRE is trying to achieve and suggestions for recognition in the content and approaches to SRE.</p

Dust Streamers in the Virgo Galaxy M86 from Ram Pressure Stripping of its Companion VCC 882

The giant elliptical galaxy M86 in Virgo has a ~28 kpc long dust trail inside its optical halo that points toward the nucleated dwarf elliptical galaxy, VCC 882. The trail seems to be stripped material from the dwarf. Extinction measurements suggest that the ratio of the total gas mass in the trail to the blue luminosity of the dwarf is about unity, which is comparable to such ratios in dwarf irregular galaxies. The ram pressure experienced by the dwarf galaxy in the hot gaseous halo of M86 was comparable to the internal gravitational binding energy density of the presumed former gas disk in VCC 882. Published numerical models of this case are consistent with the overall trail-like morphology observed here. Three concentrations in the trail may be evidence for the predicted periodicity of the mass loss. The evaporation time of the trail is comparable to the trail age obtained from the relative speed of the galaxies and the trail length. Thus the trail could be continuously formed from stripped replenished gas if the VCC 882 orbit is bound. However, the high gas mass and the low expected replenishment rate suggest that this is only the first stripping event. Implications for the origin of nucleated dwarf ellipticals are briefly discussed.Comment: 22 pages, 7 figures, Astronomical Journal, August 2000, in pres

Towards improved socio-economic assessments of ocean acidification’s impacts

Ocean acidification is increasingly recognized as a component of global change that could have a wide range of impacts on marine organisms, the ecosystems they live in, and the goods and services they provide humankind. Assessment of these potential socio-economic impacts requires integrated efforts between biologists, chemists, oceanographers, economists and social scientists. But because ocean acidification is a new research area, significant knowledge gaps are preventing economists from estimating its welfare impacts. For instance, economic data on the impact of ocean acidification on significant markets such as fisheries, aquaculture and tourism are very limited (if not non-existent), and non-market valuation studies on this topic are not yet available. Our paper summarizes the current understanding of future OA impacts and sets out what further information is required for economists to assess socio-economic impacts of ocean acidification. Our aim is to provide clear directions for multidisciplinary collaborative research

Beyond 'Global Production Networks': Australian Fashion Week's Trans-Sectoral Synergies

When studies of industrial organisation are informed by commodity chain, actor network, or global production network theories and focus on tracing commodity flows, social networks, or a combination of the two, they can easily overlook the less routine trans-sectoral associations that are crucial to the creation and realisation of value. This paper shifts attention to identifying the sites at which diverse specialisations meet to concentrate and amplify mutually reinforcing circuits of value. These valorisation processes are demonstrated in the case of Australian Fashion Week, an event in which multiple interests converge to synchronize different expressions of fashion ideas, actively construct fashion markets and enhance the value of a diverse range of fashionable commodities. Conceptualising these interconnected industries as components of a trans-sectoral fashion complex has implications for understanding regional development, world cities, production location, and the manner in which production systems “touch down” in different places

Near-source observations and modeling of the Kuril Islands tsunamis of 15 November 2006 and 13 January 2007

International audienceTwo major earthquakes near the Central Kuril Islands (Mw=8.3 on 15 November 2006 and Mw=8.1 on 13 January 2007) generated trans-oceanic tsunamis recorded over the entire Pacific Ocean. The strongest oscillations, exceeding several meters, occurred near the source region of the Kuril Islands. Tide gauge records for both tsunamis have been thoroughly examined and numerical models of the events have been constructed. The models of the 2006 and 2007 events include two important advancements in the simulation of seismically generated tsunamis: (a) the use of the finite failure source models by Ji (2006, 2007) which provide more detailed information than conventional models on spatial displacements in the source areas and which avoid uncertainties in source extent; and (b) the use of the three-dimensional Laplace equation to reconstruct the initial tsunami sea surface elevation (avoiding the usual shallow-water approximation). The close agreement of our simulated results with the observed tsunami waveforms at the open-ocean DART stations support the validity of this approach. Observational and model findings reveal that energy fluxes of the tsunami waves from the source areas were mainly directed southeastward toward the Hawaiian Islands, with relatively little energy propagation into the Sea of Okhotsk. A marked feature of both tsunamis was their high-frequency content, with typical wave periods ranging from 2?3 to 15?20 min. Despite certain similarities, the two tsunamis were essentially different and had opposite polarity: the leading wave of the November 2006 trans-oceanic tsunami was positive, while that for the January 2007 trans-oceanic tsunami was negative. Numerical modeling of both tsunamis indicates that, due to differences in their seismic source properties, the 2006 tsunami was more wide-spread but less focused than the 2007 tsunami

Collective tests for quantum nonlocality

Pairs of spin-1/2 particles are prepared in a Werner state (namely, a mixture of singlet and random components). If the random component is large enough, the statistical results of spin measurements that may be performed on each pair separately can be reproduced by an algorithm involving local ``hidden'' variables. However, if several such pairs are tested simultaneously, a violation of the Clauser-Horne-Shimony-Holt inequality may occur, and no local hidden variable model is compatible with the results.Comment: 14 pages, LaTeX, 1 figure on separate pag