By means of the present geometrical and dynamical observational data, it is very hard to establish, from a statistical perspective, a clear preference among the vast majority of the proposed models for the dynamical dark energy and/or modified gravity theories alternative with respect to the $Λ$CDM scenario. On the other hand, on scales much smaller than present Hubble scale, there are possibly detectable differences in the growth of the matter perturbations for different modes of the perturbations, even in the context of the $Λ$CDM model. Here, we analyze the evolution of the dark matter perturbations in the context of $Λ$CDM and some dynamical dark energy models involving future cosmological singularities, such as the sudden future singularity and the finite scale factor singularity. We employ the Newtonian gauge formulation for the derivation of the perturbation equations for the growth function, and we abandon both the sub-Hubble approximation and the slowly varying potential assumption. We apply the Fisher Matrix approach to three future planned galaxy surveys e.g., DESI, Euclid, and WFirst-2.4. With the mentioned surveys on hand, only with the dynamical probes, we will achieve multiple goals: $1.$ the improvement in the accuracy of the determination of the $fσ_{8}$ will give the possibility to discriminate between the $Λ$CDM and the alternative dark energy models even in the scale-independent approach; $2.$ it will be possible to test the goodness of the scale-independence finally, and also to quantify the necessity of a scale dependent approach to the growth of the perturbations, in particular using surveys which encompass redshift bins with scales $k<0.005\,h$ Mpc$^{-1}$; $3.$ the scale-dependence itself might add much more discriminating power in general, but further advanced surveys will be needed.
Phantom dark energy as a natural selection of evolutionary processes $\hat{\rm a}$ $\textit{la}$ $\textit{genetic algorithm}$ and cosmological tensions
Implications from simulated strong gravitational lensing systems: constraining cosmological parameters using Gaussian Processes
强引力透镜系统(SGL)将宇宙学信息编码为源/透镜距离比$\mathcal{D}_{\rm obs}=\mathcal{D}_{\rm ls}/\mathcal{D}_{\rm s}$,可用于精确约束宇宙学参数。在本文中,基于未来的测量390强透镜系统从即将到来的LSST调查,我们已经成功地重建的距离比$\mathcal{D}_{\rm obs}$(与源红移$z_s\sim 4.0$),直接从数据,而不假设任何参数的形式。最近开发的方法的基础上,模型无关的重建方法,高斯过程(GP)被用于我们的研究这些强透镜系统。我们的研究结果表明,独立测量的物质密度参数($Ω_m$),可以预期从这样强的透镜统计。更具体地说,可以预期在一致性$Λ$ CDM模型中以$ΔΩ_m\sim0.015$的精度估计$Ω_m$,该模型提供了与普朗克2015结果相当的$Ω_m$约束。在修正的引力理论(DGP)框架下,未来LSST巡天的390个可探测星系透镜体将导致$ΔΩ_m\sim0.030$的严格拟合。\textbf{Finally, we have discussed three possible sources of systematic errors (sample incompleteness, the determination of length of lens redshift bin, and t…
Halving and Doubling: Boosting the Detection of Relativistic Effects in the Galaxy Bispectrum with Optimal Subsample Selection
Università degli Studi di Torino(都灵大学);INFN – Istituto Nazionale di Fisica Nucleare, Sezione di Torino(意大利国家核物理研究所都灵分部);INAF – Istituto Nazionale di Astrofisica, Osservatorio Astrofisico di Torino(意大利国家天体物理学研究所都灵天文台);University of the Western Cape(西开普敦大学);Queen Mary University of London(伦敦玛丽女王大学);Università degli Studi di Ferrara(费拉拉大学)
Robustness of pairwise kinematic Sunyaev-Zel'dovich effect to optical-cluster-selection bias
Ludwig-Maximilians-Universität(路德维希-马克西米利安大学);Max-Planck-Institut für extraterrestrische Physik (MPE)(马克斯·普朗克地外物理研究所);Institute of Astronomy and Astrophysics, Academia Sinica (ASIAA)(中央研究院天文及天文物理研究所);Excellence Cluster ORIGINS(ORIGINS卓越集群);University of Pennsylvania(宾夕法尼亚大学);Max-Planck-Institut für Astrophysik(马克斯·普朗克天体物理研究所);University of Chicago(芝加哥大学);Southern Methodist University(南方卫理公会大学);European Southern Observatory(欧洲南方天文台);University of Arizona(亚利桑那大学)
FlowSN: Neural Simulation-Based Inference under Realistic Selection Effects applied to Supernova Cosmology
University of Cambridge(剑桥大学);National Center for Supercomputing Applications(国家超级计算应用中心);University of Illinois Urbana-Champaign(伊利诺伊大学厄巴纳-香槟分校);University of Chicago(芝加哥大学)