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Gauge-invariant metric fluctuations from NKK theory of gravity: de Sitter expansion

Jose Edgar Madriz Aguilar·Mariano Anabitarte·Mauricio Bellini
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Abstract

In this paper we study gauge-invariant metric fluctuations from a Noncompact Kaluza-Klein (NKK) theory of gravity in a de Sitter expansion. We recover the well known result $δρ/ρ\simeq 2Φ$, obtained from the standard 4D semiclassical approach to inflation. The spectrum for these fluctuations should be dependent of the fifth (spatial-like) coordinate.

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Jose Edgar Madriz Aguilar, Mariano Anabitarte, Mauricio Bellini. 2005-10-20. Gauge-invariant metric fluctuations from NKK theory of gravity: de Sitter expansion. https://doi.org/10.1016/j.physletb.2005.10.037

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