Largescale tests of the DvaliGabadadzePorrati model
Abstract
The selfaccelerating braneworld model (DGP) can be tested from measurements of the expansion history of the Universe and the formation of structure. Current constraints on the expansion history from supernova luminosity distances, the cosmic microwave background (CMB), and the Hubble constant exclude the simplest flat DGP model at about 3{sigma}. Even including spatial curvature, the bestfit open DGP model is a marginally poorer fit to the data than flat {lambda}CDM. Moreover, its substantially different expansion history raises serious challenges for the model from structure formation. A dark energy model with the same expansion history would predict a highly significant discrepancy with the baryon oscillation measurement due the high Hubble constant required. For the DGP model to satisfy this constraint new nonlinear phenomena must correct this discrepancy. Likewise the large enhancement of CMB anisotropies at the lowest multipoles due to the ISW effect would require either a cutoff in the initial power or new phenomena at the crossover scale. A prediction that is robust to both possibilities is that highredshift galaxies should be substantially correlated with the CMB through the ISW effect. This correlation should provide a sharp test of the DGP model in the future.
 Authors:
 Kavli Institute for Cosmological Physics, Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States)
 (United States)
 Publication Date:
 OSTI Identifier:
 21020149
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.064003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANISOTROPY; BARYONS; BRANES; CORRELATIONS; COSMOLOGY; GALAXIES; HUBBLE EFFECT; MULTIPOLES; NONLINEAR PROBLEMS; NONLUMINOUS MATTER; OSCILLATIONS; QUANTUM FIELD THEORY; RELICT RADIATION; SUPERNOVAE; UNIVERSE
Citation Formats
Song, YongSeon, Hu, Wayne, Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637, Sawicki, Ignacy, and Department of Physics, University of Chicago, Chicago, Illinois 60637. Largescale tests of the DvaliGabadadzePorrati model. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.064003.
Song, YongSeon, Hu, Wayne, Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637, Sawicki, Ignacy, & Department of Physics, University of Chicago, Chicago, Illinois 60637. Largescale tests of the DvaliGabadadzePorrati model. United States. doi:10.1103/PHYSREVD.75.064003.
Song, YongSeon, Hu, Wayne, Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637, Sawicki, Ignacy, and Department of Physics, University of Chicago, Chicago, Illinois 60637. Thu .
"Largescale tests of the DvaliGabadadzePorrati model". United States.
doi:10.1103/PHYSREVD.75.064003.
@article{osti_21020149,
title = {Largescale tests of the DvaliGabadadzePorrati model},
author = {Song, YongSeon and Hu, Wayne and Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637 and Sawicki, Ignacy and Department of Physics, University of Chicago, Chicago, Illinois 60637},
abstractNote = {The selfaccelerating braneworld model (DGP) can be tested from measurements of the expansion history of the Universe and the formation of structure. Current constraints on the expansion history from supernova luminosity distances, the cosmic microwave background (CMB), and the Hubble constant exclude the simplest flat DGP model at about 3{sigma}. Even including spatial curvature, the bestfit open DGP model is a marginally poorer fit to the data than flat {lambda}CDM. Moreover, its substantially different expansion history raises serious challenges for the model from structure formation. A dark energy model with the same expansion history would predict a highly significant discrepancy with the baryon oscillation measurement due the high Hubble constant required. For the DGP model to satisfy this constraint new nonlinear phenomena must correct this discrepancy. Likewise the large enhancement of CMB anisotropies at the lowest multipoles due to the ISW effect would require either a cutoff in the initial power or new phenomena at the crossover scale. A prediction that is robust to both possibilities is that highredshift galaxies should be substantially correlated with the CMB through the ISW effect. This correlation should provide a sharp test of the DGP model in the future.},
doi = {10.1103/PHYSREVD.75.064003},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}

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Cascading Gravity: Extending the DvaliGabadadzePorrati Model to Higher Dimension
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Crossing w=1 by a single scalar on a DvaliGabadadzePorrati brane
Recent type Ia supernovae data seem to favor a dark energy model whose equation of state w(z) crosses 1, which is a much more amazing problem than the acceleration of the universe. Either the case that w(z) evolves from above 1 to below 1 or the case that w(z) runs from below 1 to above 1, is consistent with present data. In this paper we show that it is possible to realize the crossing behaviors of both of the two cases by only a single scalar field in frame of DvaliGabadadzePorrati braneworld. At the same time we prove that theremore »