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Cosmological perturbations in the inflationary Universe

Winfried Zimdahl
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Abstract

Previously defined covariant and gauge-invariant perturbation variables, representing, e.g., the fractional spatial energy density gradient on hypersurfaces of constant expansion, are used to simplify the linear perturbation analysis of a classical scalar field. With the help of conserved quantities on large scales we establish an exact first-order relation between comoving fluid energy density perturbations at `reentry' into the horizon and corresponding scalar field energy density perturbations at the first Hubble scale crossing during an early de Sitter phase of a standard inflationary scenario.

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BibTeXRIS

Winfried Zimdahl. 1997-07-29. Cosmological perturbations in the inflationary Universe. https://doi.org/10.1103/physrevd.56.3357

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