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We illustrate how recently improved low-redshift cosmological measurements can tighten constraints on neutrino properties. In particular we examine the impact of the assumed cosmological model on the constraints. We first consider the new…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-14 Beth A. Reid , Licia Verde , Raul Jimenez , Olga Mena

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

A novel evolutionary method is introduced that can be used for constraining the parameters and theoretical models of Cosmology. The newly proposed algorithm, which is inherently parallel by design, is able to obtain the full potential of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 Supin P Surendran , Aiswarya A , Rinsy Thomas , Minu Joy

Detecting dark energy dynamics is the main quest of current dark energy research. Addressing the issue demands a fully consistent analysis of CMB, large scale structure and SN-Ia data with multi-parameter freedom valid for all redshifts.…

Astrophysics · Physics 2008-11-26 P. S. Corasaniti , M. Kunz , D. Parkinson , E. J. Copeland , B. A. Bassett

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

Astrophysics · Physics 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-15 Bikash R. Dinda , Narayan Banerjee

We use updated Hubble parameter and baryon acoustic oscillation data, as well as other lower-redshift Type Ia supernova, Mg II reverberation-measured quasar, quasar angular size, H II starburst galaxy, and Amati-correlated gamma-ray burst…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-31 Shulei Cao , Bharat Ratra

In this manuscript, we investigate the constraints on dynamical vacuum models within the framework of $\Lambda(t)$CDM cosmology by assuming a parameterization of the vacuum energy density as $\rho_{\Lambda}(t)=\rho_{\Lambda 0} \left[1 +…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-14 Yerlan Myrzakulov , M. Koussour , M. Bulanbay , S. Muminov , J. Rayimbaev

The observed tension ($\sim 9\%$ difference) between the local distance ladder measurement of the Hubble constant, $H_0$, and its value inferred from the cosmic microwave background (CMB) could hint at new, exotic, cosmological physics. We…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-13 S. Dhawan , D. Brout , D. Scolnic , A. Goobar , A. G. Riess , V. Miranda

We study the dark energy equation of state as a function of redshift in a non-parametric way, without imposing any {\it a priori} $w(z)$ (ratio of pressure over energy density) functional form. As a check of the method, we test our scheme…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Sergey Postnikov , Maria Giovanna Dainotti , Xavier Hernandez , Salvatore Capozziello

Although the spin parameter of dark matter halos is well known to follow a log-normal distribution at fixed epoch, its quantitative redshift evolution - encompassing both the mean and the dispersion - remains only partially explored. Prior…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-27 Tomas Riera , Alexander Knebe , Chris Power , Robert Adriel Mostoghiu Paun , Adam Ussing

According to the perturbed Friedmann model, the difference between Hubble constant measurements in two rest frames, at leading order in velocity, is determined solely by the relative motion of the observers and remains unaffected by the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-24 Xiaoyun Shao , Carlos A. P. Bengaly

Identifying new observational probes to constrain cosmological parameters has become an important goal in modern cosmology. In this work, we explore the potential of the cosmic star formation rate density (SFRD), compiled over the redshift…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Miguel Moyses , Rafael C. Nunes

Recent works have shown that small shifts in redshift -- gravitational redshift or systematic errors -- could potentially cause a significant bias in the estimation of cosmological parameters. I aim to verify whether a theoretical…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-29 Jeong Hwa Kim

We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Dorian Araya , Cristian Castillo , Genly Leon , Juan Magaña , Angie Barr Domínguez , Miguel A. García-Aspeitia

In modern cosmology, the discovery of the universe's accelerated expansion has significantly transformed our understanding of cosmic evolution and expansion history. The unknown properties of dark energy, the driver of this acceleration,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Xincheng Zhu , Rui Xu , Dandan Xu

Adopting the low-redshift observational datasets, including the Pantheon sample of Type Ia supernovae, baryon acoustic oscillation measurements, and the tomographic Alcock-Paczynski method, we determine the Hubble constant to be…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-22 Xue Zhang , Qing-Guo Huang

We study cosmological evolution in a flat FLRW spacetime in the context of modified STEGR gravity or $f(Q)$, using an exponential two-parameter model which represents a smooth perturbative expansion around the $\Lambda$CDM model. The…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Ivan R. Vasquez , A. Oliveros

The LambdaCDM model is the most commonly accepted framework in modern cosmology. However, the local measurements of the Hubble constant, H0, via the Supernovae Type Ia (SNe Ia) calibrated on Cepheids provide a value which is in significant…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-28 M. G. Dainotti , B. De Simone , G. Montani , E. Rinaldi , M. Bogdan , K. M. Islam , A. Gangopadhyay