TY - JOUR
T1 - Probing Newton's constant on vast scales
T2 - Dvali-Gabadadze-Porrati gravity, cosmic acceleration, and large scale structure
AU - Lue, Arthur
AU - Scoccimarro, Román
AU - Starkman, Glenn D.
PY - 2004
Y1 - 2004
N2 - The nature of the fuel that drives today's cosmic acceleration is an open and tantalizing mystery. The brane-world theory of Dvali, Gabadadze, and Porrati (DGP) provides a context where late-time acceleration is driven not by some energy-momentum component (dark energy), but rather is the manifestation of the excruciatingly slow leakage of gravity off our four-dimensional world into an extra dimension. At the same time, DGP gravity alters the gravitational force law in a specific and dramatic way at cosmologically accessible scales. We derive the DGP gravitational force law in a cosmological setting for spherical perturbations at subhorizon scales and compute the growth of large-scale structures. We find that a residual repulsive force at large distances gives rise to a suppression of the growth of density and velocity perturbations. Explaining the cosmic acceleration in this framework leads to a present day fluctuation power spectrum normalization σ8≤0.8 at about the two-sigma level, in contrast with observations. We discuss further theoretical work necessary to go beyond our approximations to confirm these results.
AB - The nature of the fuel that drives today's cosmic acceleration is an open and tantalizing mystery. The brane-world theory of Dvali, Gabadadze, and Porrati (DGP) provides a context where late-time acceleration is driven not by some energy-momentum component (dark energy), but rather is the manifestation of the excruciatingly slow leakage of gravity off our four-dimensional world into an extra dimension. At the same time, DGP gravity alters the gravitational force law in a specific and dramatic way at cosmologically accessible scales. We derive the DGP gravitational force law in a cosmological setting for spherical perturbations at subhorizon scales and compute the growth of large-scale structures. We find that a residual repulsive force at large distances gives rise to a suppression of the growth of density and velocity perturbations. Explaining the cosmic acceleration in this framework leads to a present day fluctuation power spectrum normalization σ8≤0.8 at about the two-sigma level, in contrast with observations. We discuss further theoretical work necessary to go beyond our approximations to confirm these results.
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U2 - 10.1103/PhysRevD.69.124015
DO - 10.1103/PhysRevD.69.124015
M3 - Article
AN - SCOPUS:3843151404
VL - 69
JO - Physical review D: Particles and fields
JF - Physical review D: Particles and fields
SN - 1550-7998
IS - 12
M1 - 124015
ER -