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Related papers: Cosmological Constraints on $\Lambda$(t)CDM Models

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In the paper, we consider two models in which dark energy is coupled with either dust matter or dark matter, and discuss the conditions that allow more time for structure formation to take place at high redshifts. These models are expected…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-08 Shulei Cao , Tong-Jie Zhang , Xinya Wang , Tingting Zhang

The standard model of cosmology ($\Lambda$CDM) is facing a serious crisis caused by the inconsistencies in the measurements of some fundamental cosmological parameters (Hubble constant $H_{0}$ and cosmic curvature parameter $\Omega_{k}$ for…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-05 Savita Gahlaut

In this work, we present comprehensive observational constraints on the time-varying vacuum $\Lambda(t)$CDM cosmology using the latest baryon acoustic oscillation (BAO) data from Dark Energy Spectroscopic Instrument (DESI) Data Release 2…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-05 Olga Avsajanishvili

Scale-dependence is a common feature to all effective models of quantum gravity. In this paper, a cosmological model based on the scale-dependent scenario of gravity is presented. It is argued that such models, where the scale-dependence…

General Relativity and Quantum Cosmology · Physics 2021-06-23 Pedro D. Alvarez , Benjamin Koch , Cristobal Laporte , Angel Rincon

In this paper, we examine observational constraints on the power law cosmology; essentially dependent on two parameters $H_0$ (Hubble constant) and $q$ (deceleration parameter). We investigate the constraints on these parameters using the…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Sarita Rani , A. Altaibayeva , M. Shahalam , J. K. Singh , R. Myrzakulov

In this work, we consider the so-called $\Lambda(\alpha)$CDM cosmology with $\Lambda\propto\alpha^{-6}$ while the fine-structure "constant" $\alpha$ is varying. In this scenario, the accelerated expansion of the universe is driven by the…

General Relativity and Quantum Cosmology · Physics 2017-11-16 Hao Wei , Dong-Ze Xue

In light of the most recent cosmological observations, we provide new updated constraints on the slow-roll inflation in different extended scenarios beyond the $\Lambda\rm{CDM}$ cosmological model. Along with the usual six parameters, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-25 Matteo Forconi , William Giarè , Eleonora Di Valentino , Alessandro Melchiorri

We investigate an extended cosmological model motivated by the asymptotic safety of gravitational field theory, in which the matter and radiation densities and the cosmological constant receive a correction parametrized by the parameters…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 Li-Yang Gao , Ze-Wei Zhao , She-Sheng Xue , Xin Zhang

The standard cosmological model, the $\Lambda$CDM model, is the most suitable description for our universe. This framework can explain the accelerated expansion phase of the universe but still is not immune to open problems when it comes to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-01 Maria Giovanna Dainotti , Biagio De Simone , Giovanni Montani , Malgorzata Bogdan

Implications of cosmological model with a cosmological term of the form $\Lambda = \beta \frac{\ddot {a}}{a}$, where $\beta$ is a constant, are analyzed in multidimensional space time. The proper distance, the luminosity distance-redshift,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anirudh Pradhan , G. S. Khadekar , Deepak Srivastava

The current cosmological paradigm, $\Lambda$CDM, is characterized its expansive description of the history of the Universe, its deep connections to particle physics and the large amounts of data that support it. Nonetheless, $\Lambda$CDM's…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-08 Michael S. Turner

Cosmic Microwave Background (CMB) independent approaches are frequently used in the literature to provide estimates of Hubble constant ($H_0$). In this work, we report CMB independent constraints on $H_0$ in an anisotropic extension of…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 Vikrant Yadav

We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Suresh Kumar

We analyze a class of generalized inflationary models proposed in Ref. [1], known as $\beta$-exponential inflation. We show that this kind of potential can arise in the context of brane cosmology, where the field describing the size of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-15 M. A. Santos , M. Benetti , J. S. Alcaniz , F. A. Brito , R. Silva

Tensions between cosmological measurements by different surveys or probes have always been important --- and are presently much discussed --- as they may lead to evidence of new physics. Several tests have been devised to probe the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Saroj Adhikari , Dragan Huterer

We perform a detailed comparison between the Logotropic model [P.H. Chavanis, Eur. Phys. J. Plus 130 (2015) 130] and the $\Lambda$CDM model. These two models behave similarly at large (cosmological) scales up to the present. Differences…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 Pierre-Henri Chavanis , Suresh Kumar

Recent cosmological tensions, in particular, to infer the local value of the Hubble constant $H_0$, have developed new independent techniques to constrain cosmological parameters in several cosmologies. Moreover, even when the concordance…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-14 Pablo M. Maldonado Alonso , Celia Escamilla-Rivera , Rodrigo Sandoval-Orozco

The well-known tensions on the cosmological parameters $H_0$ and $\sigma_8$ within the $\Lambda$CDM cosmology shown by the Planck-CMB and LSS data are possibly due to the systematics in the data or our ignorance of some new physics beyond…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-16 Suresh Kumar , Rafael C. Nunes , Santosh Kumar Yadav

The paradigm of \Lambda CDM cosmology works impressively well and with the concept of inflation it explains the universe after the time of decoupling. However there are still a few concerns; after much effort there is no detection of dark…

General Physics · Physics 2017-03-22 B. Vlahovic

Despite the fact that a rigid $\Lambda$-term is a fundamental building block of the concordance $\Lambda$CDM model, we show that a large class of cosmological scenarios with dynamical vacuum energy density $\rho_{\Lambda}$ and/or…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-17 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez
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