Generality of singularity avoidance in superstring theory

Anisotropic case

Hiroki Yajima, Keiichi Maeda, Hidetoshi Ohkubo

    Research output: Contribution to journalArticle

    25 Citations (Scopus)

    Abstract

    In the one-loop string effective action, we study a generality of nonsingular cosmological solutions found in the isotropic and homogeneous case. We discuss Bianchi type-I and -IX spacetimes. We find that nonsingular solutions still exist in the Bianchi type-I model around nonsingular flat Friedmann solutions. On the other hand, we cannot find any nonsingular solutions in the Bianchi type-IX model. The nonexistence of a nonsingular Bianchi type-IX universe may be consistent with the analysis of Kawai, Sakagami, and Soda; i.e., the tensor-mode perturbations against a nonsingular flat Friedmann universe are unstable, because the Bianchi type-IX model is regarded as a closed Friedmann universe with a single gravitational wave. With the stability analysis of Kawai, Sakagami, and Soda, the nonsingular universe found in the isotropic case is unstable, and a singularity avoidance may not work in generic spacetimes.

    Original languageEnglish
    Article number024020
    Pages (from-to)1-10
    Number of pages10
    JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
    Volume62
    Issue number2
    Publication statusPublished - 2000 Jul 15

    Fingerprint

    Superstring
    avoidance
    string theory
    universe
    Singularity
    Space-time
    Unstable
    Effective Action
    Gravitational Waves
    Nonexistence
    Stability Analysis
    Tensor
    Strings
    Model
    gravitational waves
    Perturbation
    Closed
    strings
    tensors
    perturbation

    ASJC Scopus subject areas

    • Physics and Astronomy(all)
    • Nuclear and High Energy Physics
    • Mathematical Physics
    • Physics and Astronomy (miscellaneous)

    Cite this

    Generality of singularity avoidance in superstring theory : Anisotropic case. / Yajima, Hiroki; Maeda, Keiichi; Ohkubo, Hidetoshi.

    In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 62, No. 2, 024020, 15.07.2000, p. 1-10.

    Research output: Contribution to journalArticle

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