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Related papers: Kinematic Reconstruction of $\Lambda(t)$CDM Models

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We study observational constraints on the non-metricity $f(Q)$-gravity which reproduces an exact $\Lambda$CDM background expansion history while modifying the evolution of linear perturbations. To this purpose we use Cosmic Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-29 Luís Atayde , Noemi Frusciante

We study kinetics of single species reactions ("A+A -> 0") for general local reactivity Q and dynamical exponent z (rms displacement x_t ~ t^{1/z}.) For small molecules z=2, whilst z=4,8 for certain polymer systems. For dimensions d above…

Statistical Mechanics · Physics 2009-10-31 Ben O'Shaughnessy , Dimitrios Vavylonis

Given the remarkable success of the $\Lambda$CDM model in fitting various cosmological observations, a pertinent question in assessing the phenomenological viability of modified gravity theories is whether they can reproduce an exactly…

General Relativity and Quantum Cosmology · Physics 2025-04-30 Saikat Chakraborty , Jibitesh Dutta , Daniele Gregoris , Khamphee Karwan , Wompherdeiki Khyllep

Constraining the dark energy deceleration parameter is one of the fascinating topics in the recent cosmological paradigm. This work aims to reconstruct the dark energy using parametrization of the deceleration parameter in a flat FRW…

General Relativity and Quantum Cosmology · Physics 2023-09-26 Amine Bouali , Himanshu Chaudhary , Ujjal Debnath , Alok Sardar , G. Mustafa

Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…

General Physics · Physics 2026-03-10 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

This study examines interacting quintessence dark energy models and their observational constraints for a general parameterization of the quintessence potential, which encompasses a broad range of popular potentials. Four different forms of…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-25 Nandan Roy

Assuming a simple form for the growth index gamma(z) depending on two parameters gamma_0 = gamma(z=0) and gamma_1 = gamma'(z=0), we show that these parameters can be constrained using background expansion data. We explore systematically the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-31 Radouane Gannouji , David Polarski

Considering the recent advances, the weak correlation between the massive Kalb-Ramond and the Proca interacting models is investigated by means of a set of complementary quantum field techniques beyond the semi-classical approach. A…

High Energy Physics - Theory · Physics 2024-03-14 G. B. de Gracia

We present a detailed and pedagogical analysis of recent cosmological data, including CMB, BAO, SnIa and the recent local measurement of $H_0$. We thus obtain constraints on the parameters of standard dark energy parameterizations,…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-15 Anastasios Theodoropoulos , Leandros Perivolaropoulos

If the dark energy is modelled as a relativistic elastic solid then the standard CDM and $\Lambda$CDM models, as well as lattice configurations of cosmic strings or domain walls, are points in the two-dimensional parameter space $(w,c_{\rm…

Astrophysics · Physics 2010-12-09 Richard A. Battye , Adam Moss

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

We present a new model-independent method to determine the spatial curvature and to mitigate the circularity problem affecting the use of quasars as distance indicators. The cosmic-chronometer measurements are used to construct the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-29 Jun-Jie Wei , Fulvio Melia

$\phi$CDM models provide an alternative to the standard $\Lambda$CDM paradigm, while being physically better motivated. These models lead to a time-dependent speed of sound for dark energy that is difficult to replicate by $w$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-29 Olga Avsajanishvili , Gennady Y. Chitov , Tina Kahniashvili , Sayan Mandal , Lado Samushia

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

Diagram series expansion for lattice models with a localized nonlinearity can be renormalized so that diagram vertexes become irreducible vertex parts of certain impurity model. Thus renormalized series converges well in the very opposite…

Statistical Mechanics · Physics 2007-05-23 A. N. Rubtsov

In our recent work [1] on lattice QCD calculation of the baryon leading-twist LCDAs within the framework of LaMET, a novel hybrid renormalization scheme is implemented for octet baryon quasi-DAs, yielding reliable results across both…

High Energy Physics - Lattice · Physics 2026-05-15 Mu-Hua Zhang

This paper studies both $\Lambda$CDM and CDM models under the \"uber gravity theory, named \"u$\Lambda$CDM and \"uCDM respectively. We report bounds over their parameter phase-space using several cosmological data, in particular, the recent…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 Gustavo A. Concha Valdez , Claudia Quintanilla , Miguel A. García-Aspeitia , A. Hernández-Almada , V. Motta

We present a general parametrization for energy density of a quintessence field, a minimally coupled canonical scalar field which rolls down slowly during the late time. This parametrization can mimic all classes of quintessence dynamics,…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-09 Shiriny Akthar , Md. Wali Hossain

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Muhammad Omer Farooq

A particular choice of renormalization, within the simplifications provided by the non-perturbative property of Effective Locality, leads to a completely finite, renormalized theory of QCD, in which all correlation functions can, in…

High Energy Physics - Theory · Physics 2015-05-20 H. M. Fried , P. H. Tsang , Y. Gabellini , T. Grandou , Y. -M. Sheu
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