41,366 research outputs found

    A Classical String in Lifshitz-Vaidya Geometry

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    We study the time evolution of the expectation value of a rectangular Wilson loop in strongly anisotropic time-dependent plasma using gauge-gravity duality. The corresponding gravity theory is given by describing time evolution of a classical string in the Lifshitz-Vaidya background. We show that the expectation value of the Wilson loop oscillates about the value of the static potential with the same parameters after the energy injection is over. We discuss how the amplitude and frequency of the oscillation depend on the parameters of the theory. In particular, by raising the anisotropy parameter, we observe that the amplitude and frequency of the oscillation increase.Comment: 19 pages, 5 figure

    Forward-Backward Asymmetry in B→Xde+e−B\to X_d e^+e^-

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    The Forward-backward asymmetry in the angular distribution of e+e−e^+e^- is studied in the process B→e+e−andBˉ→Xˉde+e−B\to e^+e^- and \bar{B}\to \bar{X}_d e^+e^- . The possibility of observing CP violation through the asymmetries in these two processes is examined.Comment: 5 pages, latex formatte

    O(αs)O(\alpha_s) Corrections to B→Xse+e−B \to X_s e^+ e^- Decay in the 2HDM

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    O(αs)O(\alpha_s) QCD corrections to the inclusive B→Xse+e−B \to X_s e^+ e^- decay are investigated within the two - Higgs doublet extension of the standard model (2HDM). The analysis is performed in the so - called off-resonance region; the dependence of the obtained results on the choice of the renormalization scale is examined in details. It is shown that O(αs)O(\alpha_s) corrections can suppress the B→Xse+e−B \to X_s e^+ e^- decay width up to 1.5÷31.5 \div 3 times (depending on the choice of the dilepton invariant mass ss and the low - energy scale μ\mu). As a result, in the experimentally allowed range of the parameters space, the relations between the B→Xse+e−B \to X_s e^+ e^- branching ratio and the new physics parameters are strongly affected. It is found also that though the renormalization scale dependence of the B→Xse+e−B \to X_s e^+ e^- branching is significantly reduced, higher order effects in the perturbation theory can still be nonnegligible.Comment: 16 pages, latex, including 6 figures and 3 table

    Juxtaposition of Women, Culture, and Nature in Alice Walker's Possessing the Secret of Joy

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    The present paper focuses on the tradition of women's circumsicion in the African tribe of Olinkan in Alice Walker's Possesing the Secret of Joy. The Olinkans are asked by the white settlers to stop women's mutilation, but Olinkan men continue this custom stealthily to ensure their patriarchial dominance. This novel is a complicated juxtaposition of two different types of oppression: one by White male colonizers over an African native land, and the other one by the native Olinkan men over native women. In this juxtaposition women and land are both victims exploited and manipulated by men, no matter Black or White. This novel is also seen as a fertile ground to analyze the dual domination of both nature and women by the Olinkan men and White colonizers who are both trying to impose their androcentric rules that are created to dominate women and land, respectively

    Two Higgs Doublet Model and Lepton Polarization in the B -> K tau+ tau- Decay

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    The decay width, forward-backward asymmetry and tau lepton longitudinal and transversal polarization for the exclusive (B -> K tau^+ tau^-) decay in a two Higgs doublet model are computed. It is shown that the forward-backward asymmetry and longitudinal polarization of the tau lepton are very effective tools for establishing new physics.Comment: 25 pages, 20 figures, LaTeX formatte

    Quantum Einstein's Equations and Constraints Algebra

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    In this paper we shall address this problem: Is quantum gravity constraints algebra closed and what are the quantum Einstein equations. We shall investigate this problem in the de-Broglie--Bohm quantum theory framework. It is shown that the constraint algebra is weakly closed and the quantum Einstein's equations are derived.Comment: 13 pages, No figure, RevTeX. To appear in Pramana J. Phys., 200
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