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Reconstruction techniques are commonly used in cosmology to reduce complicated nonlinear behaviours to a more tractable linearized system. We study a new reconstruction technique that uses the Moving-Mesh algorithm to estimate the…

宇宙学与河外天体物理 · 物理学 2017-06-21 Qiaoyin Pan , Ue-Li Pen , Derek Inman , Hao-Ran Yu

In this paper, three kinds of simple parameterized deceleration parameters $q(z)=a+\frac{b z}{1+z}$, $q(z)=a+\frac{b z}{(1+z)^2}$ and $q(z)={1/2}+\frac{a z+b}{(1+z)^2}$ are reconstructed from the latest Sne Ia Gold dataset, observational…

天体物理学 · 物理学 2009-11-13 Lixin Xu , Chengwu Zhang , Baorong Chang , Hongya Liu

This review summarizes recent attempts to reconstruct the expansion history of the Universe and to probe the nature of dark energy. Reconstruction methods can be broadly classified into parametric and non-parametric approaches. It is…

天体物理学 · 物理学 2008-11-26 Varun Sahni , Alexei Starobinsky

We propose a straightforward and model independent methodology for characterizing the sensitivity of CMB and other experiments to wiggles, irregularities, and features in the primordial power spectrum. Assuming that the primordial…

宇宙学与河外天体物理 · 物理学 2015-06-11 Christopher Gauthier , Martin Bucher

Current constraints on models of galaxy evolution rely on morphometric catalogs extracted from multi-band photometric surveys. However, these catalogs are altered by selection effects that are difficult to model, that correlate in non…

天体物理仪器与方法 · 物理学 2017-09-06 Sébastien Carassou , Valérie de Lapparent , Emmanuel Bertin , Damien Le Borgne

We examine the prospects for measurement of the Hubble parameter $H_0$ via observation of the secular parallax of other galaxies due to our own motion relative to the cosmic microwave background rest frame. Peculiar velocities make distance…

宇宙学与河外天体物理 · 物理学 2023-01-10 Nicolas C. Ferree , Emory F. Bunn

From a phenomenological point of view, we analyze the dynamics of the Universe at late times by introducing a polynomial and hyperbolic bulk viscosity into the Einstein field equations respectively. We constrain their free parameters using…

综合物理 · 物理学 2019-10-01 A. Hernández-Almada

A new parametrization of the Hubble parameter is proposed to explore the issue of the cosmological landscape. The constraints on model parameters are derived through the Markov Chain Monte Carlo (MCMC) method by employing a comprehensive…

宇宙学与河外天体物理 · 物理学 2024-05-06 L. Sudharani , Kazuharu Bamba , N. S. Kavya , V. Venkatesha

In the absence of complex astrophysical processes that characterize the reionization era, the 21-cm emission from neutral hydrogen (HI) in the post-reionization epoch is believed to be an excellent tracer of the underlying dark matter…

宇宙学与河外天体物理 · 物理学 2015-05-30 Tapomoy Guha Sarkar , Sourav Mitra , Suman Majumdar , Tirthankar Roy Choudhury

In this work, two models of metric $f(R)$ gravity in the Jordan frame are investigated as a dynamical description of the late-time cosmic expansion using binned Type Ia Supernovae data. The aim is to provide an explanation for the effective…

广义相对论与量子宇宙学 · 物理学 2026-04-15 A. Valletta , G. Montani , M. G. Dainotti , E. Fazzari

We assess the performance of a perturbation theory inspired method for inferring cosmological parameters from the joint measurements of galaxy-galaxy weak lensing ($\Delta\Sigma$) and the projected galaxy clustering ($w_{\rm p}$). To do…

宇宙学与河外天体物理 · 物理学 2020-10-21 Sunao Sugiyama , Masahiro Takada , Yosuke Kobayashi , Hironao Miyatake , Masato Shirasaki , Takahiro Nishimichi , Youngsoo Park

Varying fundamental constants (VFC) [e.g., the fine-structure constant, $\alpha_{\rm EM}$] can arise in numerous extended cosmologies. Through their effect on the decoupling of baryons and photons during last scattering and reionisation,…

宇宙学与河外天体物理 · 物理学 2021-10-13 Luke Hart , Jens Chluba

Time-delay cosmology offers an alternative approach to measuring the Hubble constant ($H_0$), which is distinct from the cosmic distance ladder and cosmic microwave background radiation methods. In this study, we present an improved strong…

宇宙学与河外天体物理 · 物理学 2025-12-01 Yuting Liu , Masamune Oguri

The errors of cosmological data generated from complex processes, such as the observational Hubble parameter data (OHD) and the Type Ia supernova (SN Ia) data, cannot be accurately modeled by simple analytical probability distributions,…

宇宙学与河外天体物理 · 物理学 2021-06-17 Yu-Chen Wang , Yuan-Bo Xie , Tong-Jie Zhang , Hui-Chao Huang , Tingting Zhang , Kun Liu

We show how to obtain constraints on $\beta=f/b$, the ratio of the matter growth rate and the bias that quantifies the linear redshift-space distortions, that are independent of the cosmological model, using multiple tracers of large-scale…

宇宙学与河外天体物理 · 物理学 2019-06-19 L. Raul Abramo , Luca Amendola

By using recent $H(z)$ and SNe Ia data, we reconstruct the evolution of kinematic parameters $H(z)$, $q(z)$, jerk and snap, using a model-independent, non-parametric method, namely, the Gaussian Processes. Throughout the present analysis,…

宇宙学与河外天体物理 · 物理学 2024-01-29 J. F. Jesus , D. Benndorf , S. H. Pereira , A. A. Escobal

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

天体物理学 · 物理学 2009-10-31 Wayne Hu , Max Tegmark

Inflation predicts that the Universe is spatially flat. The Planck 2018 measurements of the cosmic microwave background anisotropy favour a spatially closed universe at more than 2$\sigma$ confidence level. We use model independent methods…

宇宙学与河外天体物理 · 物理学 2021-05-07 Yingjie Yang , Yungui Gong

We investigate the ability of state-of-the-art redshift-space distortions models for the galaxy anisotropic two-point correlation function \xi(r_p, \pi), to recover precise and unbiased estimates of the linear growth rate of structure f,…

宇宙学与河外天体物理 · 物理学 2015-06-04 Sylvain de la Torre , Luigi Guzzo

The apparent magnitude-redshift data of SNe Ia call for modifications in the standard model energy densities. Under the circumstance that this modification cannot be limited to the addition of a mere cosmological constant, a serious…

天体物理学 · 物理学 2009-12-30 Moncy V. John
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