Bibcode
Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Battaner, E.; Battye, R.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Heavens, A.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huang, Z.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H. et al.
Bibliographical reference
Astronomy and Astrophysics, Volume 594, id.A14, 31 pp.
Advertised on:
9
2016
Journal
Citations
781
Refereed citations
705
Description
We study the implications of Planck data for models of dark energy (DE)
and modified gravity (MG) beyond the standard cosmological constant
scenario. We start with cases where the DE only directly affects the
background evolution, considering Taylor expansions of the equation of
state w(a), as well as 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 and find that it has to be
below ~2% (at 95% confidence) of the critical density, even when forced
to play a role for z < 50 only. 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 background constraints
from 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 (expansion of
the equation of state, early DE, general potentials in minimally-coupled
scalar fields or principal component analysis) are in agreement with
ΛCDM. When testing models that also change perturbations (even
when the background is fixed to ΛCDM), some tensions appear in a
few scenarios: the maximum one found is ~2σ for Planck TT+lowP
when parameterizing observables related to the gravitational potentials
with a chosen time dependence; the tension increases to, at most,
3σ when external data sets are included. It however disappears
when including CMB lensing.