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Tensor perturbations in high-curvature string backgrounds

M. Gasperini
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Abstract

We derive a generalized equation for the evolution of tensor perturbations in a cosmological background, taking into account higher-curvature contributions and a tree-level coupling to the dilaton in the string frame. The equation is obtained by perturbing the gravi-dilaton string effective action, expanded up to first order in $α'$. The $α'$ corrections can modify the low-energy perturbation spectrum, but the modifications are shown to be small when the background curvature keeps constant in the string frame.

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BibTeXRIS

M. Gasperini. 1997-04-15. Tensor perturbations in high-curvature string backgrounds. https://doi.org/10.1103/physrevd.56.4815

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