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Gravitational waves in non-singular string cosmologies

C. Cartier·E. J. Copeland·M. Gasperini
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Abstract

We study the evolution of tensor metric fluctuations in a class of non-singular models based on the string effective action, by including in the perturbation equation the higher-derivative and loop corrections needed to regularise the background solutions. We discuss the effects of such higher-order corrections on the final graviton spectrum, and we compare the results of analytical and numerical computations.

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C. Cartier, E. J. Copeland, M. Gasperini. 2001-01-05. Gravitational waves in non-singular string cosmologies. https://doi.org/10.1016/s0550-3213(01)00182-1

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