75,896 research outputs found

    Reply To "Comment on 'Quantum String Seal Is Insecure' "

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    In Phys. Rev. A. 76, 056301 (2007), He claimed that the proof in my earlier paper [Phys. Rev. A 75, 012327 (2007)] is insufficient to conclude the insecurity of all quantum string seals because my measurement strategy cannot obtain non-trivial information on the sealed string and escape detection at the same time. Here, I clarify that our disagreement comes from our adoption of two different criteria on the minimum amount of information a quantum string seal can reveal to members of the public. I also point out that He did not follow my measurement strategy correctly.Comment: 2 page

    Centers and Cocenters of 00-Hecke algebras

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    In this paper, we give explicit descriptions of the centers and cocenters of 00-Hecke algebras associated to finite Coxeter groups.Comment: 13 pages, a mistake in 4.2 is correcte

    Magnetic properties of a spin-3 Chromium condensate

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    We study the ground state properties of a spin-3 Cr condensate subject to an external magnetic field by numerically solving the Gross-Piteavskii equations. We show that the widely adopted single-mode approximation is invalid under a finite magnetic field. In particular, a phase separation like behavior may be induced by the magnetic field. We also point out the possible origin of the phase separation phenomenon.Comment: 6 pages, 5 figure

    Energy-Conserving Lattice Boltzmann Thermal Model in Two Dimensions

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    A discrete velocity model is presented for lattice Boltzmann thermal fluid dynamics. This model is implemented and tested in two dimensions with a finite difference scheme. Comparison with analytical solutions shows an excellent agreement even for wide temperature differences. An alternative approximate approach is then presented for traditional lattice transport schemes

    Investigation of Partial Discharge in Solid Dielectric under DC Voltage

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    A partial discharge, or PD, is defined as an electrical discharge that is localized within only a part of the insulation between two separated conductors. Recent research on PD mainly focuses on the study of PD characteristics under AC voltage. Compared with DC, PD under AC is more serious and can be easily detected in terms of PD number. As the results of these concentrated research, the understanding of PD under AC condition has been significantly improved and features extracted from PD measurements have been used to diagnose the insulation condition of many power apparatus. Recently, rapid development in HVDC transmission and power grids connection, and widely applied DC cable and gas-insulated switchgear because of their benefit in long distance usage lead to an increasing concern about PD under DC. However, available study for the condition is little and related research is therefore necessary and essential for understanding the lifetime and reliability of apparatus. <br/

    CP Violation in Fermion Pair Decays of Neutral Boson Particles

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    We study CP violation in fermion pair decays of neutral boson particles with spin 0 or 1. We study a new asymmetry to measure CP violation in η,KLμ+μ\eta, K_L \rightarrow \mu^+\mu^- decays and discuss the possibility of measuring it experimentally. For the spin-1 particles case, we study CP violation in the decays of J/ψJ/\psi to SU(3)SU(3) octet baryon pairs. We show that these decays can be used to put stringent constraints on the electric dipole moments of Λ\Lambda, Σ\Sigma and Ξ\Xi.Comment: 14p, OZ-93/22, UM-93/89, OITS 51

    New perspective on space and time from Lorentz violation

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    I present a brief review on space and time in different periods of physics, and then talk on the nature of space and time from physical arguments. I discuss the ways to test such a new perspective on space and time through searching for Lorentz violation in some physical processes. I also make an introduce to a newly proposed theory of Lorentz violation from basic considerations.Comment: 10 latex pages. Plenary talk at First LeCosPA Symposium: Towards Ultimate Understanding of the Universe (LeCosPA2012), National Taiwan University, Taipei, Taiwan, February 6-9, 201

    Ti-rich and Cu-poor grain-boundary layers of CaCu3_3Ti4_4O12_{12} detected by x-ray photoelectron spectroscopy

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    Cleaved and polished surfaces of CaCu3_3Ti4_4O12_{12} ceramics have been investigated by x-ray photoelectron spectroscopy (XPS) and energy dispersive x-ray spectroscopy (EDX), respectively. While EDX technique shows the identical CaCu3_3Ti4_4O12_{12} stoichiometry for the two surfaces, XPS indicates that the cleaved surface with grain-boundary layers is remarkably Ti-rich and Cu-poor. The core-level spectrum of Cu 2pp unambiguously shows the existence of monovalent copper only for the cleaved surface. Possible grain-boundary structure and its formation are discussed.Comment: 8 pages, 3 figure

    CP violation in J/ψΛΛˉJ/\psi \rightarrow \Lambda \bar \Lambda

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    We study CP violation in J/ψΛΛˉJ/\psi \rightarrow \Lambda \bar{\Lambda} decay. This decay provides a good place to look for CP violation. Some observables are very sensitive to the Λ\Lambda electric dipole moment dΛd_\Lambda and therefore can be used to improve the experimental upper bound on dΛd_\Lambda. CP violations in the lepton pair decays of J/ψJ/\psi and Υ\Upsilon are also discussed.Comment: 8 pages, RevTex, UM-P-92/113, OZ-92/3