5,595 research outputs found

    Asymptotic Spectral Measures, Quantum Mechanics, and E-theory

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    We study the relationship between POV-measures in quantum theory and asymptotic morphisms in the operator algebra E-theory of Connes-Higson. This is done by introducing the theory of "asymptotic" PV-measures and their integral correspondence with positive asymptotic morphisms on locally compact spaces. Examples and applications involving various aspects of quantum physics, including quantum noise models, semiclassical limits, strong deformation quantizations, and pure half-spin particles, are also discussed.Comment: For journal version, see http://link.springer.de/link/service/journals/00220/bibs/2226001/22260041.ht

    On C*-algebras and K-theory for infinite-dimensional Fredholm Manifolds

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    Let M be a smooth Fredholm manifold modeled on a separable infinite-dimensional Euclidean space E with Riemannian metric g. Given an (augmented) Fredholm filtration F of M by finite-dimensional submanifolds (M_n), we associate to the triple (M, g, F) a non-commutative direct limit C*-algebra A(M, g, F) = lim A(M_n) that can play the role of the algebra of functions vanishing at infinity on the non-locally compact space M. The C*-algebra A(E), as constructed by Higson-Kasparov-Trout for their Bott periodicity theorem for infinite dimensional Euclidean spaces, is isomorphic to our construction when M = E. If M has an oriented Spin_q-structure (1 <= q <=\infty), then the K-theory of this C*-algebra is the same (with dimension shift) as the topological K-theory of M defined by Mukherjea. Furthermore, there is a Poincare' duality isomorphism of this K-theory of M with the compactly supported K-homology of M, just as in the finite-dimensional spin setting.Comment: 27 pages. Uses Xy-PiC. Accepted for publication in Topology and its Application

    An assessment of plankton populations, toxic cyanobacteria, and potential impact of introduced marine alewife (Alosa pseudoharengus) in Pawtuckaway Lake, New Hampshire

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    A field study was conducted during the summer, 2005 to evaluate the lake water quality and planktonic communities in Pawtuckaway Lake, NH. Of special concern was the condition of the plankton populations since the lake had been subjected to introductions of adult sea-run alewife Overall water quality ranged from mesotrophic to eutrophic based on total phosphorus (8-31 !g L-1), chlorophyll a (max South, 5.0 !g L-1) and Secchi disk transparency (max North 5.1 m, min South 2.8 m). Of the three sites sampled, Fundy, North and South, Fundy (Zmax \u3c 2 m) did not stratify and had the highest concentrations of total phosphorus, followed by North and South sites, respectively. North and South sites stratified throughout the summer and developed anoxic hypolimnia, with the most severe oxygen deficit at the North site Potentially toxigenic cyanobacteria were detected at all three sites. Throughout the summer, the concentrations of the cyanotoxin microcystin in the lake were well above the average for NH lakes. Lakewater concentrations of microcystins exceeded WHO drinking water standards (1000 ng L-1) at the North site (1204.0 ng L-1) on July 21. The two dominant cyanobacteria were Anabaena spp.. and Microcystis aeruginosa. Oscillatoria (Planktothrix) were also present, but only rarely and therefore were probably were not responsible for most of the microcystins present in the lakewater

    Apollo experience report: Battery subsystem

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    Experience with the Apollo command service module and lunar module batteries is discussed. Significant hardware development concepts and hardware test results are summarized, and the operational performance of batteries on the Apollo 7 to 13 missions is discussed in terms of performance data, mission constraints, and basic hardware design and capability. Also, the flight performance of the Apollo battery charger is discussed. Inflight data are presented

    What is Consciousness For?

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    What is Consciousness For? Lee Pierson and Monroe Trout Copyright © 2005 Abstract: The answer to the title question is, in a word, volition. Our hypothesis is that the ultimate adaptive function of consciousness is to make volitional movement possible. All conscious processes exist to subserve that ultimate function. Thus, we believe that all conscious organisms possess at least some volitional capability. Consciousness makes volitional attention possible; volitional attention, in turn, makes volitional movement possible. There is, as far as we know, no valid theoretical argument that consciousness is needed for any function other than volitional movement and no convincing empirical evidence that consciousness performs any other ultimate function. Consciousness, via volitional action, increases the likelihood that an organism will direct its attention, and ultimately its movements, to whatever is most important for its survival and reproduction
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