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Author |
Di Valentino, E.; Melchiorri, A.; Mena, O.; Vagnozzi, S. |
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Title |
Nonminimal dark sector physics and cosmological tensions |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
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Volume |
101 |
Issue |
6 |
Pages |
063502 - 20pp |
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Keywords |
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Abstract |
We explore whether nonstandard dark sector physics might be required to solve the existing cosmological tensions. The properties we consider in combination are (a) an interaction between the dark matter and dark energy components and (b) a dark energy equation of state w different from that of the canonical cosmological constant w = -1. In principle, these two parameters are independent. In practice, to avoid early-time, superhorizon instabilities, their allowed parameter spaces are correlated. Moreover, a clear degeneracy exists between these two parameters in the case of cosmic microwave background (CMB) data. We analyze three classes of extended interacting dark energy models in light of the 2019 Planck CMB results and Cepheid-calibrated local distance ladder H-0 measurements of Riess et al. (R19), as well as recent baryon acoustic oscillation (BAO) and type Ia supernovae (SNeIa) distance data. We find that in quintessence coupled dark energy models, where w > -1, the evidence for a nonzero coupling between the two dark sectors can surpass the 5 sigma significance. Moreover, for both Planck + BAO or Planck + SNeIa, we find a preference for w > -1 at about three standard deviations. Quintessence models are, therefore, in excellent agreement with current data when an interaction is considered. On the other hand, in phantom coupled dark energy models, there is no such preference for a nonzero dark sector coupling. All the models we consider significantly raise the value of the Hubble constant, easing the H-0 tension. In the interacting scenario, the disagreement between Planck thorn BAO and R19 is considerably reduced from 4.3 sigma in the case of the Lambda cold dark matter (Lambda CDM) model to about 2.5 sigma. The addition of low-redshift BAO and SNeIa measurements leaves, therefore, some residual tension with R19 but at a level that could be justified by a statistical fluctuation. Bayesian evidence considerations mildly disfavor both the coupled quintessence and phantom models, while mildly favoring a coupled vacuum scenario, even when late-time datasets are considered. We conclude that nonminimal dark energy cosmologies, such as coupled quintessence, phantom, or vacuum models, are still an interesting route toward softening existing cosmological tensions, even when low-redshift datasets and Bayesian evidence considerations are taken into account. |
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Address |
[Di Valentino, Eleonora] Univ Manchester, Jodrell Bank Ctr Astrophys, Sch Phys & Astron, Oxford Rd, Manchester M13 9PL, Lancs, England, Email: eleonora.divalentino@manchester.ac.uk; |
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Amer Physical Soc |
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English |
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Series Volume |
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ISSN |
2470-0010 |
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Conference |
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Notes |
WOS:000517964500003 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4309 |
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Author |
Yang, W.Q.; Di Valentino, E.; Mena, O.; Pan, S.; Nunes, R.C. |
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Title |
All-inclusive interacting dark sector cosmologies |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
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Volume |
101 |
Issue |
8 |
Pages |
083509 - 15pp |
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Keywords |
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Abstract |
In this paper we explore possible extensions of interacting dark energy cosmologies, where dark energy and dark matter interact nongravitationally with one another. In particular, we focus on the neutrino sector, analyzing the effect of both neutrino masses and the effective number of neutrino species. We consider the Planck 2018 legacy release data combined with several other cosmological probes, finding no evidence for new physics in the dark radiation sector. The current neutrino constraints from cosmology should therefore be regarded as robust, as they are not strongly dependent on the dark sector physics, once all the available observations are combined. Namely, we find a total neutrino mass g, < 0.15 eV and a number of effective relativistic degrees of freedom N-eff = 3.03(-0.33)(+0.33), both at 95% C.L., which are close to those obtained within the ACDM cosmology, M-v < 0.12 eV and N-eff = (+0.36)(-0.35), for the same data combination. |
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Address |
[Yang, Weiqiang] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: d11102004@163.com; |
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Amer Physical Soc |
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English |
Summary Language |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2470-0010 |
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Conference |
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Notes |
WOS:000523633500002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4359 |
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Author |
Yang, W.Q.; Di Valentino, E.; Mena, O.; Pan, S. |
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Title |
Dynamical dark sectors and neutrino masses and abundances |
Type |
Journal Article |
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Year |
2020 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
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Volume |
102 |
Issue |
2 |
Pages |
023535 - 17pp |
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Keywords |
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Abstract |
We investigate generalized interacting dark matter-dark energy scenarios with a time-dependent coupling parameter, allowing also for freedom in the neutrino sector. The models are tested in the phantom and quintessence regimes, characterized by equations of state, w(x) < -1 and w(x) > -1, respectively. Our analyses show that for some of the scenarios, the existing tensions on the Hubble constant H-0 and on the clustering parameter S-8 can be significantly alleviated. The relief is either due to (a) a dark energy component which lies within the phantom region or (b) the presence of a dynamical coupling in quintessence scenarios. The inclusion of massive neutrinos into the interaction schemes does not affect either the constraints on the cosmological parameters or the bounds on the total number or relativistic degrees of freedom N-eff, which are found to be extremely robust and, in general, strongly consistent with the canonical prediction N-eff = 3.045. The most stringent bound on the total neutrino mass M-nu is M-nu, < 0.116 eV and it is obtained within a quintessence scenario in which the matter mass-energy density is only mildly affected by the presence of a dynamical dark sector coupling. |
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Address |
[Yang, Weiqiang] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: d11102004@163.com; |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Conference |
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Notes |
WOS:000550997900008 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4472 |
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Author |
Di Valentino, E.; Gariazzo, S.; Mena, O.; Vagnozzi, S. |
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Title |
Soundness of dark energy properties |
Type |
Journal Article |
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Year |
2020 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages |
045 - 45pp |
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Keywords |
supernova type Ia – standard candles; dark energy experiments; cosmological parameters from CMBR; cosmological parameters from LSS |
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Abstract |
Type Ia Supernovae (SNeIa) used as standardizable candles have been instrumental in the discovery of cosmic acceleration, usually attributed to some form of dark energy (DE). Recent studies have raised the issue of whether intrinsic SNeIa luminosities might evolve with redshift. While the evidence for cosmic acceleration is robust to this possible systematic, the question remains of how much the latter can affect the inferred properties of the DE component responsible for cosmic acceleration. This is the question we address in this work. We use SNeIa distance moduli measurements from the Pantheon and JLA samples. We consider models where the DE equation of state is a free parameter, either constant or time-varying, as well as models where DE and dark matter interact, and finally a model-agnostic parametrization of effects due to modified gravity (MG). When SNeIa data are combined with Cosmic Microwave Background (CMB) temperature and polarization anisotropy measurements, we find strong degeneracies between parameters governing the SNeIa systematics, the DE parameters, and the Hubble constant H-0. These degeneracies significantly broaden the DE parameter uncertainties, in some cases leading to O(sigma) shifts in the central values. However, including low-redshift Baryon Acoustic Oscillation and Cosmic Chronometer measurements, as well as CMB lensing measurements, considerably improves the previous constraints, and the only remaining effect of the examined systematic is a less than or similar to 40% broadening of the uncertainties on the DE parameters. The constraints we derive on the MG parameters are instead basically unaffected by the systematic in question. We therefore confirm the overall soundness of dark energy properties. |
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Address |
[Di Valentino, Eleonora] Univ Manchester, Sch Phys & Astron, Jodrell Bank Ctr Astrophys, Oxford Rd, Manchester M13 9PL, Lancs, England, Email: eleonora.divalentino@mancher.ac.uk; |
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Corporate Author |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
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Conference |
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Notes |
WOS:000551883400049 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4475 |
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Author |
Yang, W.Q.; Di Valentino, E.; Pan, S.; Mena, O. |
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Title |
Emergent Dark Energy, neutrinos and cosmological tensions |
Type |
Journal Article |
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Year |
2021 |
Publication |
Physics of the Dark Universe |
Abbreviated Journal |
Phys. Dark Universe |
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Volume |
31 |
Issue |
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Pages |
100762 - 9pp |
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Keywords |
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Abstract |
The Phenomenologically Emergent Dark Energy model, a dark energy model with the same number of free parameters as the flat Lambda CDM, has been proposed as a working example of a minimal model which can avoid the current cosmological tensions. A straightforward question is whether or not the inclusion of massive neutrinos and extra relativistic species may spoil such an appealing phenomenological alternative. We present the bounds on M-nu and N-eff and comment on the long standing H-0 and sigma(8) tensions within this cosmological framework with a wealth of cosmological observations. Interestingly, we find, at 95% confidence level, and with the most complete set of cosmological observations, M-nu similar to 0.21(-0.14)(+0.15) eV and N-eff = 3.03 +/- 0.32 i.e. an indication for a non-zero neutrino mass with a significance above 2 sigma. The well known Hubble constant tension is considerably easened, with a significance always below the 2 sigma level. (C) 2020 Elsevier B.V. All rights reserved. |
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Address |
[Yang, Weiqiang] Liaoning Normal Univ, Dept Phys, Dalian 116029, Peoples R China, Email: d11102004@163.com; |
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Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2212-6864 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000630235100022 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4752 |
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