Cluster-void degeneracy breaking: Neutrino properties and dark energy

Sahlén, Martin

doi:10.1103/physrevd.99.063525

Cited by 41 publications

(42 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Indeed recent work showed that the cosmological bounds on M ν are weaker when one enlarges the parameter space to other values of w(z) including phantom values w < −1. In fact there exists a well-known degeneracy between the DE EoS w and the sum of the three active neutrino masses M ν [66,[99][100][101][102][103][104][105][106][107][108][109][110][111][112][113][114]. However, the main result of our paper is that the cosmological bounds on neutrino masses in fact become more restrictive for the case of a DE component with w(z) ≥ −1 than for the standard ΛCDM case of w = −1.…”

Section: Introductionmentioning

confidence: 85%

Constraints on the sum of the neutrino masses in dynamical dark energy models with w(z)≥−1 are tighter than those obtained in Λ

et al. 2018

View full text Add to dashboard Cite

We explore cosmological constraints on the sum of the three active neutrino masses Mν in the context of dynamical dark energy (DDE) models with equation of state (EoS) parametrized as a function of redshift z by w(z) = w0 + wa z/(1 + z), and satisfying w(z) ≥ −1 for all z. We make use of Cosmic Microwave Background data from the Planck satellite, Baryon Acoustic Oscillations measurements, and Supernovae Ia luminosity distance measurements, and perform a Bayesian analysis. We show that, within these models, the bounds on Mν do not degrade with respect to those obtained in the ΛCDM case; in fact the bounds are slightly tighter, despite the enlarged parameter space. We explain our results based on the observation that, for fixed choices of w0 , wa such that w(z) ≥ −1 (but not w = −1 for all z), the upper limit on Mν is tighter than the ΛCDM limit because of the well-known degeneracy between w and Mν. The Bayesian analysis we have carried out then integrates over the possible values of w0-wa such that w(z) ≥ −1, all of which correspond to tighter limits on Mν than the ΛCDM limit. We find a 95% credible interval (C.I.) upper bound of Mν < 0.13 eV. This bound can be compared with the 95% C.I. upper bounds of Mν < 0.16 eV, obtained within the ΛCDM model, and Mν < 0.41 eV, obtained in a DDE model with arbitrary EoS (which allows values of w < −1). Contrary to the results derived for DDE models with arbitrary EoS, we find that a dark energy component with w(z) ≥ −1 is unable to alleviate the tension between high-redshift observables and direct measurements of the Hubble constant H0. Finally, in light of the results of this analysis, we also discuss the implications for DDE models of a possible determination of the neutrino mass ordering by laboratory searches.

show abstract

Section: Introductionmentioning

confidence: 85%

Constraints on the sum of the neutrino masses in dynamical dark energy models with w(z)≥−1 are tighter than those obtained in Λ

et al. 2018

View full text Add to dashboard Cite

show abstract

“…when the dark energy equation of state is allowed to vary), see e.g. [18,22,23,29,30,[43][44][45][46][47][48] for recent investigations, although there are exceptions to this statement: for instance, allowing for a time-varying dark energy component, but forcing it to lie in the non-phantom region (i.e. w(z) ≥ −1), actually results in tighter upper limits on M ν [49].…”

Section: Introductionmentioning

confidence: 99%

Bias due to neutrinos must not uncorrect'd go

Vagnozzi

Brinckmann

Archidiacono

et al. 2018

J. Cosmol. Astropart. Phys.

View full text Add to dashboard Cite

It is a well known fact that galaxies are biased tracers of the distribution of matter in the Universe. The galaxy bias is usually factored as a function of redshift and scale, and approximated as being scale-independent on large, linear scales. In cosmologies with massive neutrinos, the galaxy bias defined with respect to the total matter field (cold dark matter, baryons, and non-relativistic neutrinos) also depends on the sum of the neutrino masses Mν , and becomes scale-dependent even on large scales. This effect has been usually neglected given the sensitivity of current surveys. However, it becomes a severe systematic for future surveys aiming to provide the first detection of non-zero Mν . The effect can be corrected for by defining the bias with respect to the density field of cold dark matter and baryons, rather than the total matter field. In this work, we provide a simple prescription for correctly mitigating the neutrino-induced scale-dependent bias effect in a practical way. We clarify a number of subtleties regarding how to properly implement this correction in the presence of redshift-space distortions and non-linear evolution of perturbations. We perform a Markov Chain Monte Carlo analysis on simulated galaxy clustering data that match the expected sensitivity of the Euclid survey. We find that the neutrino-induced scale-dependent bias can lead to important shifts in both the inferred mean value of Mν , as well as its uncertainty, and provide an analytical explanation for the magnitude of the shifts. We show how these shifts propagate to the inferred values of other cosmological parameters correlated with Mν , such as the cold dark matter physical density Ω cdm h 2 and the scalar spectral index ns. In conclusion, we find that correctly accounting for the neutrino-induced scale-dependent bias will be of crucial importance for future galaxy clustering analyses. We encourage the cosmology community to correctly account for this effect using the simple prescription we present in our work. The tools necessary to easily correct for the neutrino-induced scale-dependent bias will be made publicly available in an upcoming release of the Boltzmann

show abstract

“…We consider a flat wCDM cosmology with massive neutrinos described by the sum of neutrino masses m ν . The void distribution is modelled following Sahlén et al (2016), Sahlén & Silk (2018), and Sahlén (2019), also taking into account the galaxy density and bias for each survey (Yahya et al 2015;Raccanelli et al 2016c). The results are shown in Figure 35 (see caption for survey and model assumptions).…”

Section: Constraining Neutrino Properties With Ska Voidsmentioning

confidence: 99%

“…The SKA2 void number counts could improve on this, down to σ (γ 0 ) = 0.07, σ (γ 1 ) = 0.15. Using the powerful degeneracy-breaking complementarity between clusters of galaxies and voids (Sahlén et al 2016;Sahlén & Silk 2018;Sahlén 2019), SKA2 voids + Euclid clusters number counts could reach σ (γ 0 ) = 0.01, σ (γ 1 ) = 0.07.…”

Section: Radio Weak Lensingmentioning

confidence: 99%

Fundamental physics with the Square Kilometre Array

Weltman

Bull

Camera

et al. 2020

Publ. Astron. Soc. Aust.

293

169

View full text Add to dashboard Cite

The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.

show abstract

Cluster-void degeneracy breaking: Neutrino properties and dark energy

Cited by 41 publications

References 45 publications

Constraints on the sum of the neutrino masses in dynamical dark energy models with w(z)≥−1 are tighter than those obtained in Λ

Constraints on the sum of the neutrino masses in dynamical dark energy models with w(z)≥−1 are tighter than those obtained in Λ

Bias due to neutrinos must not uncorrect'd go

Fundamental physics with the Square Kilometre Array

Contact Info

Product

Resources

About