6533b81ffe1ef96bd1277305
RESEARCH PRODUCT
Uncertainty on w from large-scale structure
Wessel ValkenburgWessel ValkenburgValerio MarraMikko PääkkönenMikko Pääkkönensubject
Big BangPhysicsCosmology and Nongalactic Astrophysics (astro-ph.CO)ta114010308 nuclear & particles physicsEquation of state (cosmology)Scalar field dark matterFOS: Physical sciencesAstronomy and AstrophysicsLambda-CDM modelGeneral Relativity and Quantum Cosmology (gr-qc)Cosmological constantAstrophysics::Cosmology and Extragalactic Astrophysics01 natural sciencesGeneral Relativity and Quantum CosmologyComputational physicsThermodynamics of the universeSpace and Planetary ScienceQuantum mechanics0103 physical sciencesDark energy010303 astronomy & astrophysicsDark fluidAstrophysics - Cosmology and Nongalactic Astrophysicsdescription
We find that if we live at the center of an inhomogeneity with total density contrast of roughly 0.1, dark energy is not a cosmological constant at 95% confidence level. Observational constraints on the equation of state of dark energy, w, depend strongly on the local matter density around the observer. We model the local inhomogeneity with an exact spherically symmetric solution which features a pressureless matter component and a dark-energy fluid with constant equation of state and negligible sound speed, that reaches a homogeneous solution at finite radius. We fit this model to observations of the local expansion rate, distant supernovae and the cosmic microwave background. We conclude that the possible uncertainty from large-scale structure has to be taken into account if one wants to progress towards not just precision but also accurate cosmology.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2012-03-09 |