Can higher curvature corrections cure the singularity problem in f(R) gravity?

Tsutomu Kobayashi, Keiichi Maeda

    Research output: Contribution to journalArticle

    71 Citations (Scopus)

    Abstract

    Although f(R) modified gravity models can be made to satisfy solar system and cosmological constraints, it has been shown that they have the serious drawback of the nonexistence of stars with strong gravitational fields. In this paper, we discuss whether or not higher curvature corrections can remedy the nonexistence consistently. The following problems are shown to arise as the costs one must pay for the f(R) models that allow for neutrons stars: (i) the leading correction must be fine-tuned to have the typical energy scale μ 10-19GeV, which essentially comes from the free fall time of a relativistic star; (ii) the leading correction must be further fine-tuned so that it is not given by the quadratic curvature term. The second problem is caused because there appears an intermediate curvature scale, and laboratory experiments of gravity will be under the influence of higher curvature corrections. Our analysis thus implies that it is a challenge to construct viable f(R) models without very careful and unnatural fine-tuning.

    Original languageEnglish
    Article number024009
    JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
    Volume79
    Issue number2
    DOIs
    Publication statusPublished - 2009 Jan 5

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    curvature
    gravitation
    stars
    free fall
    solar system
    gravitational fields
    neutron stars
    tuning
    costs
    energy

    ASJC Scopus subject areas

    • Nuclear and High Energy Physics

    Cite this

    Can higher curvature corrections cure the singularity problem in f(R) gravity? / Kobayashi, Tsutomu; Maeda, Keiichi.

    In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 79, No. 2, 024009, 05.01.2009.

    Research output: Contribution to journalArticle

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