Evolution of second-order cosmological perturbations
نویسندگان
چکیده
We present a method for constructing gauge-invariant cosmological perturbations which are gaugeinvariant up to second order. As an example we give the gauge-invariant definition of the second order curvature perturbation on uniform density hypersurfaces. Using only the energy conservation equation we show that this curvature perturbation is conserved at second order on large scales for adiabatic perturbations.
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تاریخ انتشار 2008