18,770 research outputs found

    SLˉ(4,R)\bar{SL}(4,R) Embedding for a 3D World Spinor Equation

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    A generic-curved spacetime Dirac-like equation in 3D is constructed. It has, owing to the SLˉ(n,R)\bar{SL}(n,R) group deunitarizing automorphism, a physically correct unitarity and flat spacetime particle properties. The construction is achieved by embedding SLˉ(3,R)\bar{SL}(3,R) vector operator XμX_{\mu}, that plays a role of Dirac's γμ\gamma_{\mu} matrices, into SLˉ(4,R)\bar{SL}(4,R). Decomposition of the unitary irreducible spinorial SLˉ(4,R)\bar{SL}(4,R) representations gives rise to an explicit form of the infinite XμX_{\mu} matrices

    Vertex correction and Ward identity in the U(1) gauge theory with Fermi surface

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    We show that introduction of vertex corrections in the fully self-consistent ladder approximation does not modify dynamics of spinons and gauge fluctuations in the U(1) gauge theory with Fermi surface

    Time Dependent Quark Masses and Big Bang Nucleosynthesis Revisited

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    We reinvestigate the constraints from primordial nucleosynthesis on a possible time-dependent quark mass. The limits on such quark-mass variations are particularly sensitive to the adopted observational abundance constraints. Hence, in the present study we have considered updated light-element abundances and uncertainties deduced from observations. We also consider new nuclear reaction rates and an independent analysis of the influence of such quark-mass variations on the resonance properties of the important 3He(d,p)4He reaction. We find that the updated abundance and resonance constraints imply a narrower range on the possible quark-mass variations in the early universe. We also find that, contrary to previous investigations, the optimum concordance region reduces to a (95% C.L.) value of -0.005 < delta m_q/m_q < 0.007 consistent with no variation in the averaged quark mass.Comment: 9 pages, 2 figures, analytic formulae of D and 4He abundances as well as standard BBN prediction added, discussion on the 6Li production added, minor errors fixed, accepted for publication in PR

    Earnings and Dividend Announcements is there a Corroboration Effect?

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    We examine abnormal stock returns surrounding contemporaneous earnings and dividend announcements in order to determine whether investors evaluate the two announcements in relation to each other.We find that there is a statistically significant interaction effect.The abnormal return corresponding to any earnings or dividend announcement depends upon the value of the other announcement. This evidence suggests the existence of a corroborative relationship between the two announcements. Investors give more credence to unanticipated dividend increases or decreases when earnings are also above or below expectations, and vice versa.
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