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Planck 2015 results: XVIII. Background geometry and topology of the Universe

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dc.contributor.author Ade P.
dc.contributor.author Aghanim N.
dc.contributor.author Arnaud M.
dc.contributor.author Ashdown M.
dc.contributor.author Aumont J.
dc.contributor.author Baccigalupi C.
dc.contributor.author Banday A.
dc.contributor.author Barreiro R.
dc.contributor.author Bartolo N.
dc.contributor.author Basak S.
dc.contributor.author Battaner E.
dc.contributor.author Benabed K.
dc.contributor.author Benoît A.
dc.contributor.author Benoit-Lévy A.
dc.contributor.author Bernard J.
dc.contributor.author Bersanelli M.
dc.contributor.author Bielewicz P.
dc.contributor.author Bock J.
dc.contributor.author Bonaldi A.
dc.contributor.author Bonavera L.
dc.contributor.author Bond J.
dc.contributor.author Borrill J.
dc.contributor.author Bouchet F.
dc.contributor.author Bucher M.
dc.contributor.author Burigana C.
dc.contributor.author Butler R.
dc.contributor.author Calabrese E.
dc.contributor.author Cardoso J.
dc.contributor.author Catalano A.
dc.contributor.author Challinor A.
dc.contributor.author Chamballu A.
dc.contributor.author Chiang H.
dc.contributor.author Christensen P.
dc.contributor.author Church S.
dc.contributor.author Clements D.
dc.contributor.author Colombi S.
dc.contributor.author Colombo L.
dc.contributor.author Combet C.
dc.contributor.author Couchot F.
dc.contributor.author Coulais A.
dc.contributor.author Crill B.
dc.contributor.author Curto A.
dc.contributor.author Cuttaia F.
dc.contributor.author Danese L.
dc.contributor.author Davies R.
dc.contributor.author Davis R.
dc.contributor.author De Bernardis P.
dc.contributor.author De Rosa A.
dc.contributor.author De Zotti G.
dc.contributor.author Delabrouille J.
dc.contributor.author Désert F.
dc.contributor.author Diego J.
dc.contributor.author Dole H.
dc.contributor.author Donzelli S.
dc.contributor.author Doré O.
dc.contributor.author Douspis M.
dc.contributor.author Ducout A.
dc.contributor.author Dupac X.
dc.contributor.author Efstathiou G.
dc.contributor.author Elsner F.
dc.contributor.author Enßlin T.
dc.contributor.author Eriksen H.
dc.contributor.author Feeney S.
dc.contributor.author Fergusson J.
dc.date.accessioned 2018-09-19T20:05:08Z
dc.date.available 2018-09-19T20:05:08Z
dc.date.issued 2016
dc.identifier.issn 0004-6361
dc.identifier.uri https://dspace.kpfu.ru/xmlui/handle/net/142532
dc.description.abstract © ESO, 2016.Maps of cosmic microwave background (CMB) temperature and polarization from the 2015 release of Planck data provide the highestquality full-sky view of the surface of last scattering available to date. This enables us to detect possible departures from a globally isotropic cosmology. We present the first searches using CMB polarization for correlations induced by a possible non-trivial topology with a fundamental domain that intersects, or nearly intersects, the last-scattering surface (at comoving distance χrec), both via a direct scan for matched circular patterns at the intersections and by an optimal likelihood calculation for specific topologies. We specialize to flat spaces with cubic toroidal (T3) and slab (T1) topologies, finding that explicit searches for the latter are sensitive to other topologies with antipodal symmetry. These searches yield no detection of a compact topology with a scale below the diameter of the last-scattering surface. The limits on the radius i of the largest sphere inscribed in the fundamental domain (at log-likelihood ratio Δ >-5 relative to a simply-connected flat Planck best-fit model) are: i > 0.97 χrec for the T3 cubic torus; and i > 0.56 χrec for the T1 slab. The limit for the T3 cubic torus from the matched-circles search is numerically equivalent, i > 0.97 χrec at 99% confidence level from polarization data alone. We also perform a Bayesian search for an anisotropic global Bianchi VIIh geometry. In the non-physical setting, where the Bianchi cosmology is decoupled from the standard cosmology, Planck temperature data favour the inclusion of a Bianchi component with a Bayes factor of at least 2.3 units of log-evidence. However, the cosmological parameters that generate this pattern are in strong disagreement with those found from CMB anisotropy data alone. Fitting the induced polarization pattern for this model to the Planck data requires an amplitude of-0.10 ± 0.04 compared to the value of + 1 if the model were to be correct. In the physically motivated setting, where the Bianchi parameters are coupled and fitted simultaneously with the standard cosmological parameters, we find no evidence for a Bianchi VIIh cosmology and constrain the vorticity of such models to (ω/H)0 < 7.6 × 10-10 (95% CL).
dc.relation.ispartofseries Astronomy and Astrophysics
dc.subject Cosmic background radiation
dc.subject Cosmological parameters
dc.subject Cosmology: observations
dc.subject Gravitation
dc.subject Methods: data analysis
dc.subject Methods: statistical
dc.title Planck 2015 results: XVIII. Background geometry and topology of the Universe
dc.type Article
dc.relation.ispartofseries-volume 594
dc.collection Публикации сотрудников КФУ
dc.source.id SCOPUS00046361-2016-594-SID84989260734


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  • Публикации сотрудников КФУ Scopus [24551]
    Коллекция содержит публикации сотрудников Казанского федерального (до 2010 года Казанского государственного) университета, проиндексированные в БД Scopus, начиная с 1970г.

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