6,026 research outputs found

    Opposite Thermodynamic Arrows of Time

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    A model in which two weakly coupled systems maintain opposite running thermodynamic arrows of time is exhibited. Each experiences its own retarded electromagnetic interaction and can be seen by the other. The possibility of opposite-arrow systems at stellar distances is explored and a relation to dark matter suggested.Comment: To appear in Phys. Rev. Let

    Bounds on Decoherence and Error

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    When a confined system interacts with its walls (treated quantum mechanically), there is an intertwining of degrees of freedom. We show that this need not lead to entanglement, hence decoherence. It will generally lead to error. The wave function optimization required to avoid decoherence is also examined.Comment: 10 pages, plain TeX, no figure

    Imaging geometry through dynamics: the observable representation

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    For many stochastic processes there is an underlying coordinate space, VV, with the process moving from point to point in VV or on variables (such as spin configurations) defined with respect to VV. There is a matrix of transition probabilities (whether between points in VV or between variables defined on VV) and we focus on its ``slow'' eigenvectors, those with eigenvalues closest to that of the stationary eigenvector. These eigenvectors are the ``observables,'' and they can be used to recover geometrical features of VV

    A Cautious Path Forward on Accountable Care Organizations

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    The wave of new Accountable Care Organizations (ACOs), spurred by financial incentives in the Affordable Care Act, could become the latest chapter in the steady accumulation of market power by hospitals, health care systems, and physician groups. The main purpose behind forming many ACOs may not be to achieve cost savings but instead to strengthen negotiating power over purchasers in the private sector. This would be an unfortunate sequel to the waves of mergers in the 1990s when health care entities sought to counter market pressure from managed care organizations. The possibility that ACOs might further concentrate health care markets brings new urgency to understanding why provider monopolies are pernicious and to considering how government can ensure that ACOs pursue efficiency rather than market power

    Violation of the zeroth law of thermodynamics for a non-ergodic interaction

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    The phenomenon described by our title should surprise no one. What may be surprising though is how easy it is to produce a quantum system with this feature; moreover, that system is one that is often used for the purpose of showing how systems equilibrate. The violation can be variously manifested. In our detailed example, bringing a detuned 2-level system into contact with a monochromatic reservoir does not cause it to relax to the reservoir temperature; rather, the system acquires the reservoir's level-occupation-ratio

    Overbilling and Informed Financial Consent — A Contractual Solution

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    U.S. hospitals and physicians regularly charge uninsured patients and patients receiving care outside their health-plan networks far more what most health insurers pay and far more than their actual costs. Such practices have triggered over 100 lawsuits and prompted calls for pricing transparency in Congress and price regulation in several states. This Perspective argues that the theory of implied contracts, a foundation in most first-year courses in contract law, offers a useful legal and ethical mechanism for handling these troubling problems in health care billing

    Overregulation of Health Care: Musings on Disruptive Innovation Theory

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    Disruptive innovation theory provides one lens through which to describe how regulations may stifle innovation and increase costs. Basing their discussion on this theory, Curtis and Schulman consider some of the effects that regulatory controls may have on innovation in the health sector

    Relative momentum for identical particles

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    Possible definitions for the relative momentum of identical particles are considered

    Lessons From India in Organizational Innovation: A Tale of Two Heart Hospitals

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    Recent discussions in health reform circles have pinned great hopes on the prospect of innovation as the solution to the high-cost, inadequate-quality U.S. health system. But U.S. health care institutions--insurers, providers and specialists--have ceded leadership in innovation to Indian hospitals such as Care Hospital in Hyderabad and the Fortis Hospitals around New Delhi, which have U.S.-trained doctors and can perform open heart surgery for 6000(comparedto6000 (compared to 100,000 in the United States). The Indian success is a window into America\u27s stalemate with inflating costs and stagnant innovation

    Transport mechanism through metal-cobaltite interfaces

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    The resistive switching (RS) properties as a function of temperature were studied for Ag/La1x_{1-x}Srx_xCoO3_3 (LSCO) interfaces. The LSCO is a fully-relaxed 100 nm film grown by metal organic deposition on a LaAlO3_3 substrate. Both low and a high resistance states were set at room temperature and the temperature dependence of their current-voltage (IV) characteristics was mea- sured taking care to avoid a significant change of the resistance state. The obtained non-trivial IV curves of each state were well reproduced by a circuit model which includes a Poole-Frenkel element and two ohmic resistances. A microscopic description of the changes produced by the RS is given, which enables to envision a picture of the interface as an area where conductive and insulating phases are mixed, producing Maxwell-Wagner contributions to the dielectric properties.Comment: 13 pages, 5 figures, to be published in APL. Corresponding author: C. Acha ([email protected]
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