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Metric fluctuations from a NKK theory of gravity in a de Sitter expansion

Jose Edgar Madriz Aguilar·Mauricio Bellini
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Abstract

A gauge invariant metric fluctuations formalism from a non-compact Kaluza-Klein (NKK) theory of gravity is presented in this talk notes. In this analysis we recover the well-known result $\frac{delta ρ}ρ\simeq 2Φ$ obtained typically in the standard 4D semiclassical approach to inflation and also the spectrum of this fluctuations becomes dependent of the fifth (space-like) coordinate. This fact allows to establish an interval of values for the wave number associated with the fifth dimension.

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Jose Edgar Madriz Aguilar, Mauricio Bellini. 2007-07-23. Metric fluctuations from a NKK theory of gravity in a de Sitter expansion. https://arxiv.org/abs/gr-qc/0611069

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