Generality of inflation in a planar universe

Hisa Aki Shinkai, Keiichi Maeda

    Research output: Contribution to journalArticle

    7 Citations (Scopus)

    Abstract

    We study a generality of an inflationary scenario by integrating the Einstein equations numerically in a plane-symmetric spacetime. We consider the inhomogeneous spacetimes due to (i) localized gravitational waves with a positive cosmological constant Λ and (ii) an inhomogeneous inflation field Φ with a potential 12m2Φ2. For case (i), we find that any initial inhomogeneities are smoothed out even if waves collide, so that we conclude that inhomogeneity due to gravitational waves does not prevent the onset of inflation. As for case (ii), if the mean value of the inflaton field is initially as large as the condition in an isotropic and homogeneous inflationary model (i.e., the mean value is larger than several times the Planck mass), the field is soon homogenized and the universe always evolves into de Sitter spacetime. This supports the cosmic no hair conjecture in a planar universe. We also discuss the effects of an additional massless scalar field, which are introduced to set initial data in the usual analysis.

    Original languageEnglish
    Pages (from-to)6367-6378
    Number of pages12
    JournalPhysical Review D
    Volume49
    Issue number12
    DOIs
    Publication statusPublished - 1994

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    gravitational waves
    inhomogeneity
    universe
    hair
    Einstein equations
    scalars

    ASJC Scopus subject areas

    • Physics and Astronomy (miscellaneous)

    Cite this

    Generality of inflation in a planar universe. / Shinkai, Hisa Aki; Maeda, Keiichi.

    In: Physical Review D, Vol. 49, No. 12, 1994, p. 6367-6378.

    Research output: Contribution to journalArticle

    Shinkai, Hisa Aki ; Maeda, Keiichi. / Generality of inflation in a planar universe. In: Physical Review D. 1994 ; Vol. 49, No. 12. pp. 6367-6378.
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