Challenges to the DGP model from horizon-scale growth and geometry

Journal Article · Sat Nov 15 00:00:00 EST 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.103509· OSTI ID:21250884

Wenjuan, Fang; Hui, Lam ^[1]; Sheng, Wang ^[2]; Hu, Wayne ^[2]; Haiman, Zoltan ^[3]; May, Morgan ^[4]

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1. Department of Physics, Columbia University, New York, New York 10027 (United States)
2. Kavli Institute for Cosmological Physics, Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States)
3. Department of Astronomy, Columbia Universitys, New York, New York 10027 (United States)
4. Brookhaven National Laboratory, Upton, New York 11973 (United States)

We conduct a Markov Chain Monte Carlo study of the Dvali-Gabadadze-Porrati self-accelerating braneworld scenario given the cosmic microwave background (CMB) anisotropy, supernovae and Hubble constant data by implementing an effective dark energy prescription for modified gravity into a standard Einstein-Boltzmann code. We find no way to alleviate the tension between distance measures and horizon-scale growth in this model. Growth alterations due to perturbations propagating into the bulk appear as excess CMB anisotropy at the lowest multipoles. In a flat cosmology, the maximum likelihood Dvali-Gabadadze-Porrati model is nominally a 5.3{sigma} poorer fit than {lambda}CDM. Curvature can reduce the tension between distance measures but only at the expense of exacerbating the problem with growth leading to a 4.8{sigma} result that is dominated by the low multipole CMB temperature spectrum. While changing the initial conditions to reduce large-scale power can flatten the temperature spectrum, this also suppresses the large angle polarization spectrum in violation of recent results from the five-year Wilkinson Microwave Anisotropy Probe. The failure of this model highlights the power of combining growth and distance measures in cosmology as a test of gravity on the largest scales.

• OSTI ID: 21250884
• Journal Information: Physical Review. D, Particles Fields, Vol. 78, Issue 10; Other Information: DOI: 10.1103/PhysRevD.78.103509; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ANISOTROPY
COSMOLOGY
DISTURBANCES
GENERAL RELATIVITY THEORY
GRAVITATION
HUBBLE EFFECT
MARKOV PROCESS
MAXIMUM-LIKELIHOOD FIT
MONTE CARLO METHOD
MULTIPOLES
NONLUMINOUS MATTER
PERTURBATION THEORY
POLARIZATION
PROBES
RELICT RADIATION
SIMULATION
SPECTRA
SUPERNOVAE