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    Spin-2 Amplitudes in Black-Hole Evaporation

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    Quantum amplitudes for s=2s=2 gravitational-wave perturbations of Einstein/scalar collapse to a black hole are treated by analogy with s=1s=1 Maxwell perturbations. The spin-2 perturbations split into parts with odd and even parity. We use the Regge-Wheeler gauge; at a certain point we make a gauge transformation to an asymptotically-flat gauge, such that the metric perturbations have the expected falloff behaviour at large radii. By analogy with s=1s=1, for s=2s=2 natural 'coordinate' variables are given by the magnetic part Hij(i,j=1,2,3)H_{ij} (i,j=1,2,3) of the Weyl tensor, which can be taken as boundary data on a final space-like hypersurface ΣF\Sigma_F. For simplicity, we take the data on the initial surface ΣI\Sigma_I to be exactly spherically-symmetric. The (large) Lorentzian proper-time interval between ΣI\Sigma_I and ΣF\Sigma_F, measured at spatial infinity, is denoted by TT. We follow Feynman's +iϵ+i\epsilon prescription and rotate TT into the complex: TTexp(iθ)T\to{\mid}T{\mid} \exp(-i\theta), for 0<θπ/20<\theta\leq\pi/2. The corresponding complexified {\it classical} boundary-value problem is expected to be well-posed. The Lorentzian quantum amplitude is recovered by taking the limit as θ0+\theta\to 0_+. For boundary data well below the Planck scale, and for a locally supersymmetric theory, this involves only the semi-classical amplitude exp(iSclass(2)\exp(iS^{(2)}_{\rm class}, where Sclass(2)S^{(2)}_{\rm class} denotes the second-variation classical action. The relations between the s=1s=1 and s=2s=2 natural boundary data, involving supersymmetry, are investigated using 2-component spinor language in terms of the Maxwell field strength ϕAB=ϕ(AB)\phi_{AB}=\phi_{(AB)} and the Weyl spinor ΨABCD=Ψ(ABCD)\Psi_{ABCD}=\Psi_{(ABCD)}

    Grievance Procedures in the Administrative State

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    We have witnessed over the past three years and are now witnessing what some pundits refer to as a crisis of confidence in government. I am not inclined to be that dramatic. This is not to say that the tensions we are experiencing are not real. The reality of the events with which we are confronted belies our dream. Regretfully, our intuitive reaction to these tensions is emotional rather than one of critical analysis and constructive thought. Our basic problem is our way of life. Meditation, careful analysis and meticulous planning are but preludes to action. R.G.H. Siu suggests our normative role: Even when you don\u27t know what to do, do something
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