Dark energy properties from large future galaxy surveys

Abstract

Abstract. We perform a detailed forecast on how well a Euclid-like survey will be able to constrain dark energy and neutrino parameters from a combination of its cosmic shear power spectrum, galaxy power spectrum, and cluster mass function measurements. We find that the combination of these three probes vastly improves the survey's potential to measure the time evolution of dark energy. In terms of a dark energy figure-of-merit defined as (σ(w p )σ(w a )) −1 , we find a value of 690 for Euclid-like data combined with Planck-like measurements of the cosmic microwave background (CMB) anisotropies in a 10-dimensional cosmological parameter space, assuming a ΛCDM fiducial cosmology. For the more commonly used 7-parameter model, we find a figure-of-merit of 1900 for the same data combination. We consider also the survey's potential to measure dark energy perturbations in models wherein the dark energy is parameterised as a fluid with a nonstandard non-adiabatic sound speed, and find that in an optimistic scenario in which w 0 deviates by as much as is currently observationally allowed from −1, models withĉ 2 s = 10 −6 andĉ 2 s = 1 can be distinguished at more than 2σ significance. We emphasise that constraints on the dark energy sound speed from cluster measurements are strongly dependent on the modelling of the cluster mass function; significantly weaker sensitivities ensue if we modify our model to include fewer features of nonlinear dark energy clustering. Finally, we find that the sum of neutrino masses can be measured with a 1σ precision of 0.015 eV, even in complex cosmological models in which the dark energy equation of state varies with time. The 1σ sensitivity to the effective number of relativistic species N ml eff is approximately 0.03, meaning that the small deviation of 0.046 from 3 in the standard value of N ml eff due to non-instantaneous decoupling and finite temperature effects can be probed with 1σ precision for the first time.

Large-scale structure formation with massive neutrinos and dynamical dark energy

“…A similar analysis for surveys like Euclid [32] can be found in Ref. [33]. The power of purely large-scale measurements, such as baryon acoustic oscillations (BAO) is significantly reduced by the uncertainty in neutrino masses, and employing broadband galaxy power at much smaller scales becomes important in improving our ability to extract information about dark energy as well as the neutrino sector [27].…”

Hubble Parameter Measurement Constraints on the Redshift of the Deceleration–acceleration Transition, Dynamical Dark Energy, and Space Curvature

“…Currently available SN Ia, BAO, growth factor, CMB anisotropy, and other data can tighten the constraints on these parameters, and it will be interesting to study these data sets in conjunction with the H(z) data we have compiled here, but this is beyond the scope of our paper. Near-future data will also result in interesting limits (see, e.g., Podariu et al 2001a;Pavlov et al 2012;Santos et al 2013;Basse et al 2014).…”

Constraints to Dark Energy Using PADE Parameterizations

“…Moreover, the growth of cosmic structures are also affected by perturbations of DE when we deal with dynamical DE models with time varying EoS parameter w 1 de ¹ - (Erickson et al 2002;Bean & Doré 2004;Hu & Scranton 2004;Basilakos & Voglis 2007;Mota et al 2007;Ballesteros & Riotto 2008;Basilakos et al 2009aBasilakos et al , 2010Gannouji et al 2010;Sapone & Majerotto 2012;Batista & Pace 2013;Dossett & Ishak 2013;Basse et al 2014;Batista 2014;Nesseris & Sapone 2015;Pace et al 2014aPace et al , 2014bBasilakos 2015;Mehrabi et al 2015aMehrabi et al , 2015bMehrabi et al , 2015cMalekjani et al 2015Malekjani et al , 2017.…”