English
Related papers

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

200 papers

This paper examines a cosmological model of scale-dependent gravity. The gravitational action is taken to be the Einstein-Hilbert term supplemented with a cosmological constant, where the couplings, $G_k$ and $\Lambda_k$, run with the…

General Relativity and Quantum Cosmology · Physics 2024-05-29 Pedro D. Alvarez , Benjamin Koch , Cristobal Laporte , Angel Rincon

A recently proposed generalized entropy by Luciano and Saridakis extends the standard Boltzmann-Gibbs and Bekenstein-Hawking framework through a microscopically motivated construction involving two independent entropic exponents. When…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-21 Matías Leizerovich , Susana J. Landau , Giuseppe Gaetano Luciano , Andreas Papatriantafyllou , Emmanuel N. Saridakis

Assuming a spatially flat universe, we study the cosmological viability of an infrared corrected teleparallel gravity model, which accounts for late acceleration by weakening gravity at later times on cosmological distances. The theory does…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Waleed El Hanafy , Alexey Golovnev , Amr A. El-Zant

The $\Lambda$CDM model has long served as the cornerstone of modern cosmology, offering an elegant and successful framework for interpreting a wide range of cosmological observations. However, the rise of high-precision datasets has…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Manish Yadav , Archana Dixit , Anirudh Pradhan , M S Barak

Model-independent methods in cosmology has become an essential tool in order to deal with an increasing number of theoretical alternatives for explaining the late-time acceleration of the Universe. In principle, this provides a way of…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Vinicius C. Busti , Peter K. S. Dunsby , Alvaro de la Cruz-Dombriz , Diego Saez-Gomez

We construct the cosmological model to explain the cosmological constant problem. We built the extension of the standard cosmological model $\Lambda$CDM by consideration of decaying vacuum energy represented by the running cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-08 Marek Szydlowski

With the recent progresses on the Type II supernovae, we attempt to investigate whether there does exist new physics beyond the standard cosmological paradigm, i.e., the cosmological constant $\Lambda$ plus cold dark matter ($\Lambda$CDM).…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 Deng Wang

We present cosmological constraints from the combination of the full mission 9-year WMAP release and small-scale temperature data from the pre-Planck ACT and SPT generation of instruments. This is an update of the analysis presented in…

We combine new Cosmic Microwave Background (CMB) data from Planck with Baryon Acoustic Oscillation (BAO) data to constrain the Brans-Dicke (BD) theory, in which the gravitational constant $G$ evolves with time. Observations of type Ia…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-19 Ji-Xia Li , Feng-Quan Wu , Yi-Chao Li , Yan Gong , Xue-Lei Chen

Despite the outstanding achievements of modern cosmology, the classical dispute on the precise value of $H_0$, which is the first ever parameter of modern cosmology and one of the prime parameters in the field, still goes on and on after…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

In this paper, we study Friedmann cosmology with time-varying vacuum energy density in the context of Brans-Dicke theory. We consider an isotropic and homogeneous flat space, filled with a matter-dominated perfect fluid and a dynamical…

General Relativity and Quantum Cosmology · Physics 2024-01-09 C. P. Singh , Joan Sola Peracaula

We focus on the class of cosmological models with a time-evolving vacuum energy density of the form $\rho_\Lambda=C_0+C_1 H+C_2 H^2$, where $H$ is the Hubble rate. Higher powers of $H$ could be important for the early inflationary epoch,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Adria Gomez-Valent , Joan Sola

We perform a cosmographic analysis using several cosmological observables such as the luminosity distance moduli, the volume distance, the angular diameter distance and the Hubble parameter. These quantities are determined using different…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jun-Qing Xia , Vincenzo Vitagliano , Stefano Liberati , Matteo Viel

Despite the remarkable success of the $\Lambda$Cold Dark Matter ($\Lambda$CDM) cosmological model, a growing discrepancy has emerged (currently measured at the level of $\sim 4-6 \sigma$) between the value of the Hubble constant $H_0$…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Nils Schöneberg , Guillermo Franco Abellán , Andrea Pérez Sánchez , Samuel J. Witte , Vivian Poulin , Julien Lesgourgues

Finding the best parametrization for cosmological models in the absence of first-principle theories is an open question. We propose a data-driven parametrization of cosmological models given by the disentangled 'latent' representation of a…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-22 Davide Piras , Laura Herold , Luisa Lucie-Smith , Eiichiro Komatsu

We study if the discrepancy between the local and cosmological measurements of the Hubble constant $H_0$ can be reformulated as a tension in the cosmic microwave background (CMB) monopole temperature $T_0$. The latter is customarily fixed…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-23 Mikhail M. Ivanov , Yacine Ali-Haïmoud , Julien Lesgourgues

We confront the concordance (standard) model of cosmology, the spatially flat $\Lambda$CDM Universe with power-law form of the primordial spectrum with Planck CMB angular power spectrum data searching for possible smooth deviations beyond…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-30 Dhiraj Kumar Hazra , Arman Shafieloo

We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle rather than assuming it a priori. We consider the $\Lambda$CDM model endowed with a spherical…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-23 David Camarena , Valerio Marra , Ziad Sakr , Chris Clarkson

We test the theoretical predictions of several cosmological models against different observables to compare the indirect estimates of the current expansion rate of the Universe determined from model fitting with the direct measurements…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 Vladimir V. Luković , Rocco D'Agostino , Nicola Vittorio

Cosmological observables could be used to construct cosmological models, however, a fixed number of observables limited on the light cone is not enough to uniquely determine a certain model. A reconstructed spherically symmetric,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Siqi Liu , Tong-Jie Zhang