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相关论文: Model-independent reconstruction of cosmic thermod…

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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 examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance $\Lambda$CDM cosmology. Strong deviations are allowed by the data at…

宇宙学与河外天体物理 · 物理学 2019-03-19 Benjamin L'Huillier , Arman Shafieloo , Eric V. Linder , Alex G. Kim

We propose a non-parametric method of smoothing supernova data over redshift using a Gaussian kernel in order to reconstruct important cosmological quantities including H(z) and w(z) in a model independent manner. This method is shown to be…

天体物理学 · 物理学 2009-11-24 Arman Shafieloo , Ujjaini Alam , Varun Sahni , Alexei A. Starobinsky

We model the expansion history of the Universe as a Gaussian Process and find constraints on the dark energy density and its low-redshift evolution using distances inferred from the Luminous Red Galaxy (LRG) and Lyman-alpha (Ly$\alpha$)…

宇宙学与河外天体物理 · 物理学 2018-08-06 Shahab Joudaki , Manoj Kaplinghat , Ryan Keeley , David Kirkby

For the first time, we reconstruct the dark energy equation of the state parameter $w$ from the combination of background and perturbation observations, specifically combining the Hubble parameter data from cosmic chronometer observations…

宇宙学与河外天体物理 · 物理学 2024-07-15 Bikash R. Dinda , Narayan Banerjee

Cosmological parameters and dark energy (DE) behavior are generally constrained assuming \textit{a priori} models. We work out a model-independent reconstruction to bound the key cosmological quantities and the DE evolution. Through the…

宇宙学与河外天体物理 · 物理学 2025-01-22 Orlando Luongo , Marco Muccino

Reconstructing the evolution history of the dark energy equation of state parameter $w(z)$ directly from observational data is highly valuable in cosmology, since it contains substantial clues in understanding the nature of the accelerated…

宇宙学与河外天体物理 · 物理学 2016-08-31 Zhi-E Liu , Hao-Ran Yu , Tong-Jie Zhang , Yan-Ke Tang

Understanding the origin of the accelerated expansion of the Universe poses one of the greatest challenges in physics today. Lacking a compelling fundamental theory to test, observational efforts are targeted at a better characterization of…

宇宙学与河外天体物理 · 物理学 2010-12-28 Tracy Holsclaw , Ujjaini Alam , Bruno Sanso , Herbert Lee , Katrin Heitmann , Salman Habib , David Higdon

We have improved upon the method of smoothing supernovae data to reconstruct the expansion history of the universe, h(z), using two latest datasets, Gold and SNLS. The reconstruction process does not employ any parameterization and is…

天体物理学 · 物理学 2009-03-19 Arman Shafieloo

We present a model-independent reconstruction of the quintessence scalar field's dynamics-both its potential and kinetic energy-directly from the latest cosmological observations. Our analysis combines DESI DR2 baryon acoustic oscillation…

宇宙学与河外天体物理 · 物理学 2026-04-21 Shengjia Wang , Tian-Nuo Li , Tonghua Liu , Guo-Hong Du

The quintessence dark energy potential is reconstructed in a model-independent way. Reconstruction relies on a Gaussian process and on available expansion-rate data. Specifically, 40-point values of $H(z)$ are used, consisting of a 30-point…

广义相对论与量子宇宙学 · 物理学 2022-03-15 Emilio Elizalde , Martiros Khurshudyan , K. Myrzakulov , S. Bekov

We present a model--independent reconstruction of the normalized dark energy density function, $X(z) \equiv \rho_{\mathrm{de}}(z)/\rho_{\mathrm{de}}(0)$, derived directly from the DES-SN5YR Type~Ia supernova sample. The analysis employs an…

宇宙学与河外天体物理 · 物理学 2025-10-23 José Blanco , Víctor H. Cárdenas , Cuauhtémoc Campuzano

In the realm of thermodynamics of apparent horizon, we construct a dark energy (DE) model from 4-parameter generalized entropy of apparent horizon in a spatially non-flat universe. In particular, considering a non-zero spatial curvature of…

广义相对论与量子宇宙学 · 物理学 2025-04-07 Sergei D. Odintsov , Simone D'Onofrio , Tanmoy Paul

Hubble constant tension, together with the recent indications of dynamical dark energy proposed from the Dark Energy Spectroscopic Instrument (DESI) baryon acoustic oscillation (BAO) measurements, poses significant challenges to the…

宇宙学与河外天体物理 · 物理学 2026-03-11 Yi-Ying Wang , Yin-Jie Li , Yi-Zhong Fan

We propose two model independent methods to obtain constraints on the transition and equivalence redshifts $z_{tr}$, $z_{eq}$. In particular, we consider $z_{tr}$ as the onset of cosmic acceleration, whereas $z_{eq}$ the redshift at which…

宇宙学与河外天体物理 · 物理学 2021-11-17 Salvatore Capozziello , Peter K. S. Dunsby , Orlando Luongo

In light of the statistical performance of cosmological observations, in this work we present an improvement on the Gaussian reconstruction of the Hubble parameter data $H(z)$ from Cosmic Chronometers, Supernovae Type Ia and Clustering…

宇宙学与河外天体物理 · 物理学 2021-07-28 Mauricio Reyes , Celia Escamilla-Rivera

The current accelerated expansion of the Universe remains ones of the most intriguing topics in modern cosmology, driving the search for innovative statistical techniques. Recent advancements in machine learning have significantly enhanced…

宇宙学与河外天体物理 · 物理学 2025-01-03 José de Jesús Velázquez , Luis A. Escamilla , Purba Mukherjee , J. Alberto Vázquez

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

宇宙学与河外天体物理 · 物理学 2018-09-05 Ivan de Martino

To probe the late evolution history of the Universe, we adopt two kinds of optimal basis systems. One of them is constructed by performing the principle component analysis (PCA) and the other is build by taking the multidimensional scaling…

宇宙学与河外天体物理 · 物理学 2016-04-08 Chao-Jun Feng , Xin-Zhou Li

In this work, we implement Gaussian process regression to reconstruct the expansion history of the universe in a model-agnostic manner, using the Pantheon-Plus SN-Ia compilation in combination with two different BAO measurements (SDSS-IV…

宇宙学与河外天体物理 · 物理学 2025-12-02 Purba Mukherjee , Anjan Ananda Sen
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