1,408 research outputs found

    Reexploration of interacting holographic dark energy model: Cases of interaction term excluding the Hubble parameter

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    In this paper, we make a deep analysis for the five typical interacting holographic dark energy models with the interaction terms Q=3βH0ρdeQ=3\beta H_{0}\rho_{\rm{de}}, Q=3βH0ρcQ=3\beta H_{0}\rho_{\rm{c}}, Q=3βH0(ρde+ρc)Q=3\beta H_{0}(\rho_{\rm{de}}+\rho_{\rm c}), Q=3βH0ρdeρcQ=3\beta H_{0}\sqrt{\rho_{\rm{de}}\rho_{\rm c}}, and Q=3βH0ρdeρcρde+ρcQ=3\beta H_{0}\frac{\rho_{\rm{de}}\rho_{c}}{\rho_{\rm{de}}+\rho_{\rm c}}, respectively. We obtain observational constraints on these models by using the type Ia supernova data (the Joint Light-curve Analysis sample), the cosmic microwave background data (Planck 2015 distance priors), the baryon acoustic oscillations data, and the direct measurement of the Hubble constant. We find that the values of χmin2\chi_{\rm min}^2 for all the five models are almost equal (around~699), indicating that the current observational data equally favor these IHDE models. In addition, a comparison with the cases of interaction term involving the Hubble parameter HH is also made.Comment: 14 pages, 6 figures. arXiv admin note: text overlap with arXiv:1710.0306

    SCAN-MUSIC: An Efficient Super-resolution Algorithm for Single Snapshot Wide-band Line Spectral Estimation

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    We propose an efficient algorithm for reconstructing one-dimensional wide-band line spectra from their Fourier data in a bounded interval [Ω,Ω][-\Omega,\Omega]. While traditional subspace methods such as MUSIC achieve super-resolution for closely separated line spectra, their computational cost is high, particularly for wide-band line spectra. To address this issue, we proposed a scalable algorithm termed SCAN-MUSIC that scans the spectral domain using a fixed Gaussian window and then reconstructs the line spectra falling into the window at each time. For line spectra with cluster structure, we further refine the proposed algorithm using the annihilating filter technique. Both algorithms can significantly reduce the computational complexity of the standard MUSIC algorithm with a moderate loss of resolution. Moreover, in terms of speed, their performance is comparable to the state-of-the-art algorithms, while being more reliable for reconstructing line spectra with cluster structure. The algorithms are supplemented with theoretical analyses of error estimates, sampling complexity, computational complexity, and computational limit

    Smarr Integral Formula of D-dimensional Stationary Spacetimes in Einstein-\AE ther-Maxwell Theroy

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    Using the Wald formalism, we investigate the thermodynamics of charged black holes in D-dimensional stationary spacetimes with or without rotations in Einstein-\ae ther-Maxwell theory. In particular, assuming the existence of a scaling symmetry of the action, we obtain the Smarr integral formula, which can be applied to both Killing and universal horizons. When restricted to 4-dimensional spherically symmetric spacetimes, previous results obtained by a different method are re-derived.Comment: No figures and tables. Phys. Let. B782 (2018) 723-72
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