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

AGUSTIN, MEMBIELA; MAURICIO, BELLINI

PHYSICS LETTERS B

Elsevier

Lugar: Amsterdam; Año: 2006 vol. 635 p. 243 - 246

0370-2693

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 /ρb depends on the coupling of Φ with δφ and the spectral index of its spectrum is 0.9483 < n1 < 1.