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Inflaton and metric fluctuations in the early universe from a 5D vacuum state

Agustin Membiela·Mauricio Bellini
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Abstract

In this letter we complete a previously introduced formalism to study the gauge-invariant metric fluctuations from a noncompact Kaluza-Klein theory of gravity, to study the evolution of the early universe. The evolution of both, metric and inflaton field fluctuations are reciprocally related. We obtain that <δρ/ρ_b$ depends on the coupling of $Φ$ with $δϕ$ and the spectral index of its spectrum is: $0.9483 < n_1 < 1$.

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Agustin Membiela, Mauricio Bellini. 2006-03-01. Inflaton and metric fluctuations in the early universe from a 5D vacuum state. https://doi.org/10.1016/j.physletb.2006.03.003

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