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Related papers: Running vacuum model versus $\Lambda$CDM -- a Baye…

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We present strong evidence for dynamical dark energy that challenges the standard $\Lambda$CDM model. Several dark energy scenarios are explored, including $\omega_0\omega_a$CDM, logarithmic, exponential, JBP, and BA parameterizations,…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Himanshu Chaudhary , Salvatore Capozziello , Subhrat Praharaj , Shibesh Kumar Jas Pacif , G. Mustafa

In this work we discuss a general approach for the dissipative dark matter considering a nonextensive bulk viscosity and taking into account the role of generalized Friedmann equations. This generalized $\Lambda$CDM model encompasses a flat…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-19 W. J. C. da Silva , H. S. Gimenes , R. Silva

Evidence accumulation models (EAMs) are an important class of cognitive models used to analyze both response time and response choice data recorded from decision-making tasks. Developments in estimation procedures have helped EAMs become…

Methodology · Statistics 2023-06-01 Viet Hung Dao , David Gunawan , Robert Kohn , Minh-Ngoc Tran , Guy E. Hawkins , Scott D. Brown

In cosmology, phenomenologically motivated expressions for running vacuum are commonly parametrized as linear functions $\Lambda(H^2)$ or $\Lambda(R)$. Such kind of models assume an equation of state for vacuum given by $\,\overline…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 E. L. D. Perico , D. A. Tamayo

The $\Lambda$CDM model faces several tensions with recent cosmological data and their increased accuracy. The mismatch between the values of the Hubble constant $H_0$ obtained from direct distance ladder measurements and from the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-03 Alain Blanchard , Jean-Yves Héloret , Stéphane Ilić , Brahim Lamine , Isaac Tutusaus

We constrain two non-flat time-evolving dark energy cosmological models by using Hubble parameter data, Type Ia supernova apparent magnitude measurements, and baryonic acoustic oscillation peak length scale observations. The inclusion of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Omer Farooq , Data Mania , Bharat Ratra

Bayesian model selection methods provide a self-consistent probabilistic framework to test the validity of competing scenarios given a set of data. We present a case study application to strong gravitational lens parametric models. Our goal…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-22 Irène Balmès , Pier-Stefano Corasaniti

We investigate the properties of the FLRW flat cosmological models in which the vacuum energy density evolves with time, $\Lambda(t)$. Using different versions of the $\Lambda(t)$ model, namely quantum field vacuum, power series vacuum and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 S. Basilakos , M. Plionis , J. Sola

Recent studies suggest that dynamical dark energy (DDE) provides a better fit to the rising affluence of modern cosmological observations than the concordance model ($\Lambda$CDM) with a rigid cosmological constant, $\Lambda$. Such is the…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-19 Adrià Gómez-Valent , Joan Solà Peracaula

The $\Lambda$-term in Einstein's equations is a fundamental building block of the `concordance' $\Lambda$CDM model of cosmology. Even though the model is not free of fundamental problems, they have not been circumvented by any alternative…

General Relativity and Quantum Cosmology · Physics 2020-08-07 Cristian Moreno-Pulido , Joan Sola

Brans-Dicke (BD) cosmology is reconsidered from an approach in which the model can be formulated in $\Lambda$CDM form, but at the expense of replacing the rigid cosmological constant $\Lambda$ with a dynamical quasivacuum component which…

General Relativity and Quantum Cosmology · Physics 2018-11-29 Javier de Cruz Perez , Joan Sola

In the present paper, the effects of viscous dark matter are analysed within the $\Lambda$CDM model. Here we consider bulk viscosity through the Israel-Stewart theory approach, leading to an effective pressure term in the continuity…

General Relativity and Quantum Cosmology · Physics 2018-12-13 Norman Cruz , Esteban Gonzalez , Samuel Lepe , Diego Saez-Chillon Gomez

We explore the properties of dark energy from recent observational data, including the Gold Sne Ia, the baryonic acoustic oscillation peak from SDSS, the CMB shift parameter from WMAP3, the X-ray gas mass fraction in cluster and the Hubble…

Astrophysics · Physics 2008-11-26 Puxun Wu , Hongwei Yu

Using the Bayesian theory of model comparison, a new cosmological model due to John and Joseph [M. V. John and K. Babu Joseph, Phys. Rev. D 61, 87304 (2000)] is compared with the standard \Omega_{\Lambda} \neq 0 cosmological model. Their…

Astrophysics · Physics 2009-11-07 Moncy V. John , J. V. Narlikar

Stochastic models of varying complexity have been proposed to describe the dispersion of particles in turbulent flows, from simple Brownian motion to complex temporally and spatially correlated models. A method is needed to compare…

Fluid Dynamics · Physics 2022-07-13 Martin T. Brolly , James R. Maddison , Aretha L. Teckentrup , Jacques Vanneste

In the presence of the gravitational field, the energy density of matter no longer coincides with its mass density. A discrepancy exists, of course, also between the associated power spectra. Within the $\Lambda$CDM model, we derive a…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Maxim Eingorn , Ezgi Yilmaz , A. Emrah Yükselci , Alexander Zhuk

We consider the perturbation dynamics for the cosmic baryon fluid and determine the corresponding power spectrum for a $\Lambda(t)$CDM model in which a cosmological term decays into dark matter linearly with the Hubble rate. The model is…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-30 R. F. vom Marttens , W. S. Hipólito-Ricaldi , W. Zimdahl

We investigate in detail some popular cosmological models in light of the latest observational data, including the Union2.1 supernovae compilation, the baryon acoustic oscillation measurements from the WiggleZ Dark Energy Survey, the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ke Shi , Yongfeng Huang , Tan Lu

In the present work we analyze two different models of interaction between dark energy and dark matter, also known as vacuum decay models or $\Lambda(t)$CDM models. In both models, when the $H_0$ parameter is constrained by the Planck…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 L. S. Brito , J. F. Jesus , A. A. Escobal , S. H. Pereira

We explores the Pantheon+SH0ES dataset to identify patterns that can discriminate between different cosmological models. We focus on determining whether the behaviour of dark energy is consistent with the standard $\Lambda$CDM model or…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-19 Simone Vilardi , Salvatore Capozziello , Massimo Brescia
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