TY - JOUR

T1 - Asymptotically safe gravity as a scalar-tensor theory and its cosmological implications

AU - Cai, Yi Fu

AU - Easson, Damien

PY - 2011/11/2

Y1 - 2011/11/2

N2 - We study asymptotically safe gravity with Einstein-Hilbert truncation taking into account the renormalization group running of both gravitational and cosmological constants. We show that the classical behavior of the theory is equivalent to a specific class of Jordan-Brans-Dicke theories with a vanishing Brans-Dicke parameter, and a potential determined by the renormalization group equation. The theory may be reformulated as an f(R) theory. In the simplest cosmological scenario, we find large-field inflationary solutions near the Planck scale where the effective field theory description breaks down. Finally, we discuss the implications of a running gravitational constant to background dynamics via cosmological perturbation theory. We show that compatibility with general relativity requires that contributions from the running gravitational constant to the stress energy tensor are taken into account in the perturbation analysis.

AB - We study asymptotically safe gravity with Einstein-Hilbert truncation taking into account the renormalization group running of both gravitational and cosmological constants. We show that the classical behavior of the theory is equivalent to a specific class of Jordan-Brans-Dicke theories with a vanishing Brans-Dicke parameter, and a potential determined by the renormalization group equation. The theory may be reformulated as an f(R) theory. In the simplest cosmological scenario, we find large-field inflationary solutions near the Planck scale where the effective field theory description breaks down. Finally, we discuss the implications of a running gravitational constant to background dynamics via cosmological perturbation theory. We show that compatibility with general relativity requires that contributions from the running gravitational constant to the stress energy tensor are taken into account in the perturbation analysis.

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U2 - 10.1103/PhysRevD.84.103502

DO - 10.1103/PhysRevD.84.103502

M3 - Article

AN - SCOPUS:82955198571

VL - 84

JO - Physical Review D - Particles, Fields, Gravitation and Cosmology

JF - Physical Review D - Particles, Fields, Gravitation and Cosmology

SN - 1550-7998

IS - 10

M1 - 103502

ER -