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Classical evolution and quantum generation in generalized gravity theories including string corrections and tachyon: Unified analyses

J. Hwang·H. Noh
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Abstract

We present cosmological perturbation theory based on generalized gravity theories including string theory correction terms and a tachyonic complication. The classical evolution as well as the quantum generation processes in these variety of gravity theories are presented in unified forms. These apply both to the scalar- and tensor-type perturbations. Analyses are made based on the curvature variable in two different gauge conditions often used in the literature in Einstein's gravity; these are the curvature variables in the comoving (or uniform-field) gauge and the zero-shear gauge. Applications to generalized slow-roll inflations and its consequent power spectra are derived in unified forms which include wide range of inflationary scenarios based on Einstein's gravity and others.

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J. Hwang, H. Noh. 2004-12-30. Classical evolution and quantum generation in generalized gravity theories including string corrections and tachyon: Unified analyses. https://doi.org/10.1103/physrevd.71.063536

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