859 research outputs found

    Maximally epistemic interpretations of the quantum state and contextuality

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    We examine the relationship between quantum contextuality (in both the standard Kochen-Specker sense and in the generalised sense proposed by Spekkens) and models of quantum theory in which the quantum state is maximally epistemic. We find that preparation noncontextual models must be maximally epistemic, and these in turn must be Kochen-Specker noncontextual. This implies that the Kochen-Specker theorem is sufficient to establish both the impossibility of maximally epistemic models and the impossibility of preparation noncontextual models. The implication from preparation noncontextual to maximally epistemic then also yields a proof of Bell's theorem from an EPR-like argument.Comment: v1: 4 pages, revTeX4.1, some overlap with arXiv:1207.7192. v2: Changes in response to referees including revised proof of theorem 1, more rigorous discussion of measure theoretic assumptions and extra introductory materia

    Design, development and evaluation of Stanford/Ames EVA prehensors

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    Space Station operations and maintenance are expected to make unprecedented demands on astronaut EVA. With Space Station expected to operate with an 8 to 10 psi atmosphere (4 psi for Shuttle operations), the effectivness of pressurized gloves is called into doubt at the same time that EVA activity levels are to be increased. To address the need for more frequent and complex EVA missions and also to extend the dexterity, duration, and safety of EVA astronauts, NASA Ames and Stanford University have an ongoing cooperative agreement to explore and compare alternatives. This is the final Stanford/Ames report on manually powered Prehensors, each of which consists of a shroud forming a pressure enclosure around the astronaut's hand, and a linkage system to transfer the motions and forces of the hand to mechanical digits attached to the shroud. All prehensors are intended for attachment to a standard wrist coupling, as found on the AX-5 hard suit prototype, so that realistic tests can be performed under normal and reduced gravity as simulated by water flotation

    Design, development and evaluation of Stanford/Ames Extra-Vehicular Activity (EVA) prehensors

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    A summary is given of progress to date on work proposed in 1983 and continued in 1985, including design iterations on three different types of manually powered prehensors, construction of functional mockups of each and culminating in detailed drawings and specifications for suit-compatible sealed units for testing under realistic conditions

    Restoration of PATH Service to Lower Manhattan

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    When the World Trade Center was destroyed the transit link connecting Lower Manhattan and New Jersey, the Port Authority’s Trans Hudson system or PATH, was cut. The PATH station, which was located beneath the WTC, was destroyed, the two tunnels under the Hudson River were flooded, and the first PATH station in New Jersey was rendered useless for train movements. Immediately after Sept 11, the re-establishment of the downtown PATH service was identified as a key element in the revitalization of Lower Manhattan. The re-establishment of PATH service required that three elements of major construction be completed. These were the construction of a new temporary PATH station in the basement of the old WTC, the complete refurbishment of the Hudson River tunnels, and creation of a temporary terminal station at Exchange Place. The new WTC PATH station is founded on footings on bedrock, while the connecting pedestrian corridors are founded on the caissons that originally supported the WTC Plaza. The reconstruction of the PATH river tunnels required the complete gutting of the tunnels to remove all the electrical systems, duct banks, and track bed, which were 100 years old. The electrical and signal systems were replaced with modern systems and the original timber tie and ballast track bed was replaced with a direct fixation rail system. In order to reconfigure the Exchange Place station into a terminal station a system of track crossovers was mined through rock on the west side of the station. The tight 18-month schedule hinged on the new tunnel lining design. The schedule would not permit construction of traditional cast-in-place concrete linings. The Port Authority selected a more rapid construction option for the final lining, fiber-reinforced, sprayed-on-concrete. To maintain schedule, traditional drill and blast mining methods were abandoned and mechanical roadheaders were used to excavate the bulk of the rock removal

    Measuring Polynomial Invariants of Multi-Party Quantum States

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    We present networks for directly estimating the polynomial invariants of multi-party quantum states under local transformations. The structure of these networks is closely related to the structure of the invariants themselves and this lends a physical interpretation to these otherwise abstract mathematical quantities. Specifically, our networks estimate the invariants under local unitary (LU) transformations and under stochastic local operations and classical communication (SLOCC). Our networks can estimate the LU invariants for multi-party states, where each party can have a Hilbert space of arbitrary dimension and the SLOCC invariants for multi-qubit states. We analyze the statistical efficiency of our networks compared to methods based on estimating the state coefficients and calculating the invariants.Comment: 8 pages, 4 figures, RevTex4, v2 references update

    A generalized no-broadcasting theorem

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    We prove a generalized version of the no-broadcasting theorem, applicable to essentially \emph{any} nonclassical finite-dimensional probabilistic model satisfying a no-signaling criterion, including ones with ``super-quantum'' correlations. A strengthened version of the quantum no-broadcasting theorem follows, and its proof is significantly simpler than existing proofs of the no-broadcasting theorem.Comment: 4 page

    Interaction and observation: categorical semantics of reactive systems trough dialgebras

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    We use dialgebras, generalising both algebras and coalgebras, as a complement of the standard coalgebraic framework, aimed at describing the semantics of an interactive system by the means of reaction rules. In this model, interaction is built-in, and semantic equivalence arises from it, instead of being determined by a (possibly difficult) understanding of the side effects of a component in isolation. Behavioural equivalence in dialgebras is determined by how a given process interacts with the others, and the obtained observations. We develop a technique to inter-define categories of dialgebras of different functors, that in particular permits us to compare a standard coalgebraic semantics and its dialgebraic counterpart. We exemplify the framework using the CCS and the pi-calculus. Remarkably, the dialgebra giving semantics to the pi-calculus does not require the use of presheaf categories

    Enhancement of the Binding Energy of Charged Excitons in Disordered Quantum Wires

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    Negatively and positively charged excitons are identified in the spatially-resolved photoluminescence spectra of quantum wires. We demonstrate that charged excitons are weakly localized in disordered quantum wires. As a consequence, the enhancement of the "binding energy" of a charged exciton is caused, for a significant part, by the recoil energy transferred to the remaining charged carrier during its radiative recombination. We discover that the Coulomb correlation energy is not the sole origin of the "binding energy", in contrast to charged excitons confined in quantum dots.Comment: 4 Fig

    Superrelativity as a unification of quantum theory and relativity(II)

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    A underlying dynamical structure for both relativity and quantum theory-``superrelativity'' has been proposed in order to overcome the well known incompatibility between these theories. The relationship between curvature of spacetime (gravity) and curvature of the projective Hilbert space of pure quantum states is established as well.Comment: 6 pages,LaTeX,In the Abstract ``proposed on order'' should be read as ``proposed in order'

    Giant cell carcinoma of the lung successfully treated with surgical resection and adjuvant vinorelbine and cisplatin

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    © 2018 Giant Cell Carcinoma of the lung, a subtype of Sarcomatoid lung cancer is a poorly differentiated Non-Small-Cell Lung Cancer. GCCL has exceptionally aggressive characteristics, and its prognosis is much poorer than any other NSCLCs. Herein, we present a rare case of Giant Cell Carcinoma of lung treated successfully with surgical resection and adjuvant vinorelbine and cisplatin. A 48-year-old African American man with a history of smoking and chronic obstructive pulmonary disease was admitted to the hospital for chief complaints of shortness of breath. He was found to have a 3.5 cm × 3.3 cm x 2.8 cm cavitary right upper lobe mass which turned out to be poorly differentiated Giant Cell Carcinoma with extensive necrosis and deemed similar to stage 1b non-small cell lung cancer. He was successfully treated with right upper lobectomy and adjuvant chemotherapy with vinorelbine and cisplatin. He was followed for seven years with no evidence of recurrent disease. Giant Cell Carcinoma\u27s existing literature is limited, and hence our case is reportable. Our case is unique because of the better outcome which we believe might be the result of early detection and treatment with surgical resection along with adjuvant chemotherapy. More studies are needed to deeply understand the need for adjuvant chemotherapy in stage 1 b GCCL, and proper guidelines are required for the indications of adjuvant chemotherapy in Stage 1b GCCL
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