10-1051-0004-6361-201525814.pdf (5.19 MB)
Planck 2015 results. XIV. Dark energy and modified gravity
journal contribution
posted on 2023-06-09, 04:41 authored by Antony LewisAntony Lewis, Dipak MunshiDipak Munshi, et al. The Planck CollaborationWe study the implications of Planck data for models of dark energy (DE) and modified gravity (MG), beyond the cosmological constant scenario. We start with cases where the DE only directly affects the background evolution, considering Taylor expansions of the equation of state, principal component analysis and parameterizations related to the potential of a minimally coupled DE scalar field. When estimating the density of DE at early times, we significantly improve present constraints. We then move to general parameterizations of the DE or MG perturbations that encompass both effective field theories and the phenomenology of gravitational potentials in MG models. Lastly, we test a range of specific models, such as k-essence, f(R) theories and coupled DE. In addition to the latest Planck data, for our main analyses we use baryonic acoustic oscillations, type-Ia supernovae and local measurements of the Hubble constant. We further show the impact of measurements of the cosmological perturbations, such as redshift-space distortions and weak gravitational lensing. These additional probes are important tools for testing MG models and for breaking degeneracies that are still present in the combination of Planck and background data sets. All results that include only background parameterizations are in agreement with LCDM. When testing models that also change perturbations (even when the background is fixed to LCDM), some tensions appear in a few scenarios: the maximum one found is \sim 2 sigma for Planck TT+lowP when parameterizing observables related to the gravitational potentials with a chosen time dependence; the tension increases to at most 3 sigma when external data sets are included. It however disappears when including CMB lensing.
Funding
Precision cosmological parameters : CosmoPars; G1365; EUROPEAN UNION; 616170 ERC-2013-CoG
Astrophysics and Cosmology - Sussex Consolidated Grant; G1291; STFC-SCIENCE AND TECHNOLOGY FACILITIES COUNCIL; ST/L000652/1
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- Published
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- Published version
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Astronomy and AstrophysicsISSN
0004-6361Publisher
EDP SciencesExternal DOI
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A14Volume
594Department affiliated with
- Physics and Astronomy Publications
Research groups affiliated with
- Astronomy Centre Publications
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- Yes
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- Yes
Legacy Posted Date
2017-01-12First Open Access (FOA) Date
2017-01-12First Compliant Deposit (FCD) Date
2017-01-12Usage metrics
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