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Massless and massive graviton spectra in anisotropic dilatonic braneworld cosmologies

G. De Risi
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Abstract

We consider a braneworld model in which an anisotropic brane is embedded in a dilatonic background. We solve the background solutions and study the behavior of the perturbations when the universe evolves from an inflationary Kasner phase to a Minkowski phase. We calculate the massless mode spectrum, and find that it does not differ from what expected in standard four-dimensional cosmological models. We then evaluate the spectrum of both light (ultrarelativistic) and heavy (nonrelativistic) massive modes, and find that, at high energies, there can be a strong enhancement of the Kaluza-Klein spectral amplitude, which can become dominant in the total spectrum. The presence of the dilaton, on the contrary, decrease the relative importance of the massive modes.

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G. De Risi. 2006-05-29. Massless and massive graviton spectra in anisotropic dilatonic braneworld cosmologies. https://doi.org/10.1103/physrevd.73.124015

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