12 research outputs found

    A Novel Mass Hierarchy and Discrete Excitation Spectra from Quantum-Fluctuating D-branes

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    We elaborate further on a recently proposed scenario for generating a mass hierarchy through quantum fluctuations of a single D3 brane, which represents our world embedded in a bulk five-dimensional space time. In this scenario, the quantum fluctuations of the D3-brane world in the bulk direction, quantified to leading order via a `recoil' world-sheet logarithmic conformal field theory approach, result in the dynamical appearance of a supersymmetry breaking (obstruction) scale alpha. This may be naturally taken to be at the TeV range, in order to provide a solution to the conventional gauge-hierarchy problem. The bulk spatial direction is characterized by the dynamical appearance of an horizon located at +- 1/alpha, inside which the positive energy conditions for the existence of stable matter are satisfied. To ensure the correct value of the four-dimensional Planck mass, the bulk string scale M_s is naturally found to lie at an intermediate energy scale of 10^{14} GeV. As an exclusive feature of the D3-brane quantum fluctuations (`recoil') we find that, for any given M_5, there is a discrete mass spectrum for four-dimensional Kaluza-Klein (KK) modes of bulk graviton and/or scalar fields. KK modes with masses 0 <= m < sqrt{2}alpha << M_s are found to have wavefunctions peaked, and hence localized, on the D3 brane at z=0.Comment: 21 pages latex, three eps figures incorporate

    State of the Art Methods to Project Forest Carbon Stocks

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    This special issue provides a broad range of potential methodologies, based in economics, for projecting forest carbon stocks. Papers included highlight new analyses from various economists that have projected carbon fluxes nationally and globally. Through carefully designed research, these authors have provided deep insights into methods that can be applied broadly
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