20,816 research outputs found

    Hydrodynamics of Normal Atomic Gases with Spin-orbit Coupling

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    Successful realization of spin-orbit coupling in atomic gases by the NIST scheme opens the prospect of studying the effects of spin-orbit coupling on many-body physics in an unprecedentedly controllable way. Here we derive the linearized hydrodynamic equations for the normal atomic gases of the spin-orbit coupling by the NIST scheme with zero detuning. We show that the hydrodynamics of the system crucially depends on the momentum susceptibilities which can be modified by the spin-orbit coupling. We reveal the effects of the spin-orbit coupling on the sound velocities and the dipole mode frequency of the gases by applying our formalism to the ideal Fermi gas. We also discuss the generalization of our results to other situations.Comment: Accepted version by Scientific Reports, 13 pages, 7 figure

    Quantum Horizons

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    Treating macro-black hole as quantum states, and using Brown-York quaselocal gravitational energy definition and Heisenberg uncertainty principle, we find out the classical horizon with singularity spreads into a quantum horizon in which the space-time is non-commutative and the spread range is determined dynamically. A Quantum Field Theory (QFT) model in curved space with quantum horizon is constructed. By using it, the black hole entropy and the Hawking temperature are calculated successfully. The ϕ\phi-field mode number is predicted and our quantum horizon model favors to support the Minimal Super-symmetric Standard Model.Comment: 7 pages, No figures, LaTeX fil

    Quantum horizon and thermodynamics of black hole

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    A semi-classical reasoning leads to the non-commutativity of space and time coordinates near the horizon of static non-extreme black hole, and renders the classical horizon spreading to {\it Quantum Horizon} . In terms of the background metric of the black hole with the {\it Quantum Horizon}, a quantum field theory in curved space without ultraviolet divergency near the horizon is formulated. In this formulism, the black hole thermodynamics is reproduced correctly without both ambiguity and additional hypothesis in the deriving the hole's Hawking radiations and entropies, and a new interesting prediction on the number of radiative field modes NN is provided. Specifically, the main results are follows: 1, Hawking radiations rightly emerge as an effect of quantum tunneling through the quantum horizon, and hence the ambiguities due to going across the singularity on the classical horizon were got rid of; 2, 't Hooft's brick wall thickness hypothesis and the boundary condition imposed for the field considered in his brick wall model were got rid of also, and related physics has been interpreted; 3, The present theory is parameter free. So, the theory has power to predict the multiplicity NN of radiative field modes according to the requirement of normalization of Hawking-Bekenstein entropy. It has been found that N162N\simeq 162, which is just in good agreement with one in the Minimal Super-symmetric Standard Model. The studies in this paper represent an attempt to reveal some physics near the horizon at Planck scale. This paper serves a brief review on the author's works on this subject.Comment: 20 pages; LaTex file; No figure. To appear in "Progress in GR and QC Research", Nova Science Pub. In

    Remote Preparation of the Two-Particle State

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    We present a scheme of remote preparation of the two-particle state by using two Einstein-Podolsky-Rosen pairs or two partial entangled two-particle states as the quantum channel. The probability of the successful remote state preparation is obtained.Comment: 4 page

    Probabilistic Dense Coding Using Non-Maximally Entangled Three-Particle State

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    We present a scheme of probabilistic dense coding via a quantum channel of non-maximally entangled three-particle state. The quantum dense coding will be succeeded with a certain probability if the sender introduces an auxiliary particle and performs a collective unitary transformation. Furthermore, the average information transmitted in this scheme is calculated.Comment: 4 page

    Cheeger estimates of Dirichlet-to-Neumann operators on infinite subgraphs of graphs

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    In this paper, we study the Dirichlet-to-Neumann operators on infinite subgraphs of graphs. For an infinite graph, we prove Cheeger-type estimates for the bottom spectrum of the Dirichlet-to-Neumann operator, and the higher order Cheeger estimates for higher order eigenvalues of the Dirichlet-to-Neumann operator.Comment: 30 page

    The Weyl Integration Model for KAK decomposition of Reductive Lie Group

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    The Weyl integration model presented by An and Wang can be effectively used to reduce the integration over GG-space. In this paper, we construct an especial Weyl integration model for KAK decomposition of Reductive Lie Group and obtain an integration formula which implies that the integration of L1L^1-integrable function over reductive Lie group GG can be carried out by first integrating over each conjugacy class and then integrating over the set of conjugacy classes.Comment: 10 page

    On geometric and algebraic transience for discrete-time Markov chains

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    General characterizations of ergodic Markov chains have been developed in considerable detail. In this paper, we study the transience for discrete-time Markov chains on general state spaces, including the geometric transience and algebraic transience. Criteria are presented through establishing the drift condition and considering the first return time. As an application, we give explicit criteria for the random walk on the half line and the skip-free chain on nonnegative integers.Comment: 31 page

    Quantum entanglement and quantum nonlocality for NN-photon entangled states

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    Quantum entanglement and quantum nonlocality of NN-photon entangled states ψNm>=Nm[cosγNm>1m>2+eiθmsinγm>1Nm>2]|\psi_{N m}> =\mathcal{N}_{m}[\cos\gamma|N-m>_{1}|m>_{2} +e^{i\theta_{m}}\sin\gamma|m>_{1}|N-m>_{2}] and their superpositions are studied. We indicate that the relative phase θm\theta_{m} affects quantum nonlocality but not quantum entanglement for the state ψNm>|\psi_{N m}>. We show that quantum nonlocality can be controlled and manipulated by adjusting the state parameters of ψNm>|\psi_{N m}>, superposition coefficients, and the azimuthal angles of the Bell operator. We also show that the violation of the Bell inequality can reach its maximal value under certain conditions. It is found that quantum superpositions based on ψNm>|\psi_{N m}> can increase the amount of entanglement, and give more ways to reach the maximal violation of the Bell inequality.Comment: 6 pages, 3 figure

    Iterative Thresholded Bi-Histogram Equalization for Medical Image Enhancement

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    Enhancement of human vision to get an insight to information content is of vital importance. The traditional histogram equalization methods have been suffering from amplified contrast with the addition of artifacts and a surprising unnatural visibility of the processed images. In order to overcome these drawbacks, this paper proposes interative, mean, and multi-threshold selection criterion with plateau limits, which consist of histogram segmentation, clipping and transformation modules. The histogram partition consists of multiple thresholding processes that divide the histogram into two parts, whereas the clipping process nicely enhances the contrast by having a check on the rate of enhancement that could be tuned. Histogram equalization to each segmented sub-histogram provides the output image with preserved brightness and enhanced contrast. Results of the present study showed that the proposed method efficiently handles the noise amplification. Further, it also preserves the brightness by retaining natural look of targeted image.Comment: 8 Pages, 8 Figures, International Journal of Computer Applications (IJCA
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