6,685 research outputs found

    Canonical interpretation of Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) in the Υ\Upsilon family

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    Inspired by the new resonance Y(10750)Y(10750), we calculate the masses and two-body OZI-allowed strong decays of the higher vector bottomonium sates within both screened and linear potential models. We discuss the possibilities of Υ(10860)\Upsilon(10860) and Y(10750)Y(10750) as mixed states via the S−DS-D mixing. Our results suggest that Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) might be explained as mixed states between 5S5S- and 4D4D-wave vector bbˉb\bar{b} states. The Y(10750)Y(10750) and Υ(10860)\Upsilon(10860) resonances may correspond to the mixed states dominated by the 4D4D- and 5S5S-wave components, respectively. The mass and the strong decay behaviors of the Υ(11020)\Upsilon(11020) resonance are consistent with the assignment of the Υ(6S)\Upsilon(6S) state in the potential models.Comment: 9 pages, 4 figures. More discussions are adde

    Topolgical Charged Black Holes in Generalized Horava-Lifshitz Gravity

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    As a candidate of quantum gravity in ultrahigh energy, the (3+1)(3+1)-dimensional Ho\v{r}ava-Lifshitz (HL) gravity with critical exponent z≠1z\ne 1, indicates anisotropy between time and space at short distance. In the paper, we investigate the most general z=dz=d Ho\v{r}ava-Lifshitz gravity in arbitrary spatial dimension dd, with a generic dynamical Ricci flow parameter λ\lambda and a detailed balance violation parameter ϵ\epsilon. In arbitrary dimensional generalized HLd+1_{d+1} gravity with z≥dz\ge d at long distance, we study the topological neutral black hole solutions with general λ\lambda in z=dz=d HLd+1_{d+1}, as well as the topological charged black holes with λ=1\lambda=1 in z=dz=d HLd+1_{d+1}. The HL gravity in the Lagrangian formulation is adopted, while in the Hamiltonian formulation, it reduces to Dirac−-De Witt's canonical gravity with λ=1\lambda=1. In particular, the topological charged black holes in z=5z=5 HL6_6, z=4z=4 HL5_5, z=3,4z=3,4 HL4_4 and z=2z=2 HL3_3 with λ=1\lambda=1 are solved. Their asymptotical behaviors near the infinite boundary and near the horizon are explored respectively. We also study the behavior of the topological black holes in the (d+1)(d+1)-dimensional HL gravity with U(1)U(1) gauge field in the zero temperature limit and finite temperature limit, respectively. Thermodynamics of the topological charged black holes with λ=1\lambda=1, including temperature, entropy, heat capacity, and free energy are evaluated.Comment: 51 pages, published version. The theoretical framework of z=d HL gravity is set up, and higher curvature terms in spatial dimension become relevant at UV fixed point. Lovelock term, conformal term, new massive term, and Chern-Simons term with different critical exponent z are studie

    Solving Einstein equations using deep learning

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    Einstein field equations are notoriously challenging to solve due to their complex mathematical form, with few analytical solutions available in the absence of highly symmetric systems or ideal matter distribution. However, accurate solutions are crucial, particularly in systems with strong gravitational field such as black holes or neutron stars. In this work, we use neural networks and auto differentiation to solve the Einstein field equations numerically inspired by the idea of physics-informed neural networks (PINNs). By utilizing these techniques, we successfully obtain the Schwarzschild metric and the charged Schwarzschild metric given the energy-momentum tensor of matter. This innovative method could open up a different way for solving space-time coupled Einstein field equations and become an integral part of numerical relativity.Comment: 18 pages, 4 figure

    Dehydrogenation of Formic Acid by Heterogeneous Catalysts

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    Formic acid has recently been considered as one of the most promising hydrogen storage materials. The basic concept is briefly discussed and the research progress is detailledly reviewed on the dehydrogenation of aqueous formic acid by heterogeneous catalysts

    Hybrid statistical and mechanistic mathematical model guides mobile health intervention for chronic pain

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    Nearly a quarter of visits to the Emergency Department are for conditions that could have been managed via outpatient treatment; improvements that allow patients to quickly recognize and receive appropriate treatment are crucial. The growing popularity of mobile technology creates new opportunities for real-time adaptive medical intervention, and the simultaneous growth of big data sources allows for preparation of personalized recommendations. Here we focus on the reduction of chronic suffering in the sickle cell disease community. Sickle cell disease is a chronic blood disorder in which pain is the most frequent complication. There currently is no standard algorithm or analytical method for real-time adaptive treatment recommendations for pain. Furthermore, current state-of-the-art methods have difficulty in handling continuous-time decision optimization using big data. Facing these challenges, in this study we aim to develop new mathematical tools for incorporating mobile technology into personalized treatment plans for pain. We present a new hybrid model for the dynamics of subjective pain that consists of a dynamical systems approach using differential equations to predict future pain levels, as well as a statistical approach tying system parameters to patient data (both personal characteristics and medication response history). Pilot testing of our approach suggests that it has significant potential to predict pain dynamics given patients' reported pain levels and medication usages. With more abundant data, our hybrid approach should allow physicians to make personalized, data driven recommendations for treating chronic pain.Comment: 13 pages, 15 figures, 5 table
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