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We investigate the running cosmological constant model with dark energy linearly proportional to the Hubble parameter, $\Lambda = \sigma H + \Lambda_0$, in which the $\Lambda$CDM limit is recovered by taking $\sigma=0$. We derive the linear…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-22 Chao-Qiang Geng , Chung-Chi Lee , Kaituo Zhang

In this paper, we make a comparison for the impacts of smooth dynamical dark energy, modified gravity, and interacting dark energy on the cosmological constraints on the total mass of active neutrinos. For definiteness, we consider the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-13 Ming-Ming Zhao , Rui-Yun Guo , Dong-Ze He , Jing-Fei Zhang , Xin Zhang

The Planck collaboration has recently published maps of the Cosmic Microwave Background (CMB) radiation, in good agreement with a LCDM model, a fit especially valid for multipoles l > 40. We explore here the possibility that dark energy is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Valeria Pettorino

Yes, but only for a parameter value that makes it almost coincide with the standard model. We reconsider the cosmological dynamics of a generalized Chaplygin gas (gCg) which is split into a cold dark matter (CDM) part and a dark energy (DE)…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-03 R. F. vom Marttens , L. Casarini , W. Zimdahl , W. S. Hipólito-Ricaldi , D. F. Mota

We show that the dark energy effects can be modeled by using an \emph{Ising perfect fluid} with network interactions, whose low redshift equation of state, i.e. $\omega_0$, becomes $\omega_0=-1$ as in the $\Lambda$CDM model. In our picture,…

High Energy Physics - Theory · Physics 2015-06-15 Orlando Luongo , Damiano Tommasini

We examine a cosmological scenario where dark matter is coupled to a variable vacuum energy while baryons and photons are two decoupled components for a spatially flat Friedmann-Robertson-Walker spacetime. We apply the $\chi^{2}$ method to…

General Relativity and Quantum Cosmology · Physics 2016-04-01 Luis P. Chimento , Martín G. Richarte , Iván E. Sánchez García

Under the belief that the universe should be multi-feature and informative, we employ a model-by-model comparison method to explore the possibly largest upper bound on the swampland constant $c$. Considering the interacting quintessence…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-07 Deng Wang

In this work we provide updated constraints on coupled dark energy (CDE) cosmology with Peebles-Ratra (PR) potential and constant coupling strength $\beta$. This modified gravity scenario introduces a fifth force between dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Adrià Gómez-Valent , Valeria Pettorino , Luca Amendola

We investigate a hierarchy of interacting dark energy (IDE) models featuring a non-gravitational coupling between dark matter and dark energy. Specifically, we examine scenarios where the background interaction kernel, $Q = 3H(\delta + \eta…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-21 Mikel Artola , Ruth Lazkoz , Vincenzo Salzano

We study the minimally and non-minimally coupled scalar field models as possible alternatives for dark energy, the mysterious energy component that is driving the accelerated expansion of the universe. After discussing the dynamics at both…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Zahra Davari , Valerio Marra , Mohammad Malekjani

This study delves into the cosmological implications of the $f(Q,C)$ modified gravity framework within the context of the FLRW spacetime which offers a dynamic alternative to the standard $\Lambda$CDM cosmology. Here, we define the transit…

General Relativity and Quantum Cosmology · Physics 2024-12-03 N. Myrzakulov , Anirudh Pradhan , A. Dixit , S. H. Shekh

Testing gravity and the concordance model of cosmology, $\Lambda$CDM, at large scales is a key goal of this decade's largest galaxy surveys. Here we present a comparative study of dark matter power spectrum predictions from different…

The coupled dark energy model provides a possible approach to mitigate the coincidence problem of cosmological standard model. Here, the coupling term is assumed as $\bar{Q}=3H\xi_x\bar{\rho}_x$, which is related to the interaction rate and…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-11 Weiqiang Yang , Hang Li , Yabo Wu , Jianbo Lu

In theoretical physics, the fundamental nature and evolution mechanism of dark energy is still an open question. In General Relativity Theory, the simplest explanation for dark energy is the cosmological constant $\Lambda$. However, the…

General Relativity and Quantum Cosmology · Physics 2022-03-09 Raja Solanki , Avik De , P. K. Sahoo

There is mounting evidence from multiple cosmological probes that dark energy may be dynamical, with an equation of state that evolves over cosmic time. While this evidence is typically quantified using the Chevallier-Polarski-Linder (CPL)…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-02 Daniel A. Kessler , Luis A. Escamilla , Supriya Pan , Eleonora Di Valentino

The fundamental nature and origin of dark energy are one of the premier mysteries of theoretical physics. In General Relativity Theory, the cosmological constant $\Lambda$ is the simplest explanation for dark energy. On the other hand, the…

General Relativity and Quantum Cosmology · Physics 2022-05-27 Raja Solanki , Avik De , Sanjay Mandal , P. K. Sahoo

We present new cosmological constraints in a set of motivated extensions of the $\Lambda$CDM model using the polarization and gravitational lensing measurements from the South Pole Telescope and the Planck CMB temperature observations at…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-14 Anton Chudaykin , Dmitry Gorbunov , Nikita Nedelko

Interactions between dark matter and dark energy which result in a power-law behavior (with respect to the cosmic scale factor) of the ratio between the energy densities of the dark components (thus generalizing the LCDM model) have been…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-14 David R. Castro , Hermano Velten , Winfried Zimdahl

In this work we study a phenomenological non-gravitational interaction between dark matter and dark energy. The scenario studied in this work extends the usual interaction model proportional to the derivative of the dark component density…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-14 Josue De-Santiago , Iván E. Sánchez G. , David Tamayo

In the context of the Relativistic Quantum Geometry formalism, where the cosmological constant is promoted to a dynamical variable by attributing it a geometric interpretation as a result of a flux on the boundary of a manifold and…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Juan Ignacio Musmarra , Claudia Moreno , Rafael Hernández-Jiménez