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We present a novel cosmological framework that unifies matter creation dynamics with thermodynamic principles. Starting with a single-component fluid characterized by a constant equation of state parameter, $\omega$, we introduce a…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-27 Víctor H. Cárdenas , Samuel Lepe

This work is focused on the exploration of the thermodynamics foundations of the matter creation scenario when a generalized form of the second law of thermodynamics for this scheme is implemented. In this scenario we consider an expanding…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe

Particle creation (or annihilation) mechanisms, described by either quantum field theoretical models, or by the thermodynamics of irreversible processes, play an important role in the evolution of the early Universe, like, for example, in…

General Relativity and Quantum Cosmology · Physics 2022-11-03 T. Harko , K. Asadi , H. Moshafi , H. Sheikhahmadi

The bulk viscosity of cosmological fluid and the creation of cold dark matter both result in the generation of irreversible entropy (related to dissipative processes) in a homogeneous and isotropic universe. To consider such effects, the…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-16 Nobuyoshi Komatsu , Shigeo Kimura

We investigate entropic force cosmological models with the possibility of matter creation and energy exchange between the bulk and the horizon of a homogeneous and an isotropic flat Universe. We consider three different kinds of entropy,…

General Relativity and Quantum Cosmology · Physics 2021-07-27 Hussain Gohar , Vincenzo Salzano

We study the nonlinear growth of cosmic structure in different dark energy models, using large volume N-body simulations. We consider a range of quintessence models which feature both rapidly and slowly varying dark energy equations of…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-13 Elise Jennings , Carlton M. Baugh , Raul E. Angulo , Silvia Pascoli

In this work we explore two possible scenarios that can be considered to extend a recent proposed model by the authors known as reconstructed mimetic cosmology. This study is complemented with an statistical analysis for each case. The…

General Relativity and Quantum Cosmology · Physics 2021-07-23 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe

On the basis of a previously established scalar-tensor extension of the $\Lambda$CDM model we develop an effective fluid approach for the matter growth function. This extended $\Lambda$CDM (henceforth $e_{\Phi}\Lambda$CDM) cosmology takes…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-01 W. Zimdahl , H. E. S. Velten , W. C. Algoner

The matter creation cosmology is revisited, including the evolution of baryons and dark matter particles. The creation process affects only dark matter and not baryons. The dynamics of the $\Lambda$CDM model can be reproduced only if two…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-08 J. C. Fabris , J. A. de Freitas Pacheco , O. F. Piattella

Creation of Cold Dark Matter (CCDM), in the context of Einstein Field Equations, leads to a negative creation pressure, which can be used to explain the accelerated expansion of the Universe. Recently, it has been shown that the dynamics of…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 J. F. Jesus , F. Andrade-Oliveira

The most studied way to explain the current accelerated expansion of the universe is to assume the existence of dark energy; a new component that fill the universe, does not clumps, currently dominates the evolution, and has a negative…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Victor H. Cardenas

Two cosmological models with non-phantom matter having the same expansion of the universe as phantom cosmologies are constructed. The first model is characterized by the evolving gravitational "constant" $G$ and a dark energy component with…

Astrophysics · Physics 2009-11-10 Hrvoje Stefancic

We investigate reversible and irreversible thermodynamic processes in cosmology and their impact on the Hubble tension. Gravitationally induced adiabatic matter creation/annihilation is treated as irreversible, while energy exchange between…

General Relativity and Quantum Cosmology · Physics 2026-03-12 Hussain Gohar

Recently there have been claims on model-independent evidence of dynamical dark energy. Herein we consider a fairly general class of cosmological models with a time-evolving cosmological term of the form $\Lambda(H)=C_0+C_H H^2+C_{\dot{H}}…

General Relativity and Quantum Cosmology · Physics 2015-10-08 Joan Sola , Adria Gomez-Valent , Javier de Cruz Perez

General relativity can be reconciled with quantum field theory without quantising the geometry only if the metric evolves stochastically. In this article, we explore the consequences of such a proposal at early cosmological times. We find…

General Relativity and Quantum Cosmology · Physics 2026-05-29 Jonathan Oppenheim , Emanuele Panella , Andrew Pontzen

Cosmologies including continuous matter creation are able to reproduce the main properties of the standard $\Lambda$CDM model, in particular in cases where the particle and entropy production rates are equal. These specific models,…

General Relativity and Quantum Cosmology · Physics 2011-03-07 Alain de Roany , J. A. de Freitas Pacheco

The matter creation model of Prigogine--G\'eh\'eniau--Gunzig--Nardone is revisited in terms of a redefined creation pressure which does not lead to irreversible adiabatic evolution at constant specific entropy. With the resulting freedom to…

General Relativity and Quantum Cosmology · Physics 2022-09-15 Rossen I. Ivanov , Emil M. Prodanov

We study a cosmological model featuring evolutionary dark energy, according to the idea that the creation of its constituents arises from the gravitational field of the expanding universe, whose non-equilibrium physics is described by a…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Iolanda Navone , Maria Giovanna Dainotti , Elisa Fazzari , Giovanni Montani , Naoto Maki , Kazunori Kohri

This study explores the impact of cosmic curvature on structure formation through general relativistic first-order perturbation theory. We analyze continuity and Euler equations, incorporating cosmic curvature into Einstein equations.…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-29 Bikash R. Dinda

The Standard Model of cosmology, $\Lambda$CDM, while enormously successful, is currently unable to account for several cosmological anomalies the most prominent of which are in the measurements of the Hubble parameter and $S_8$.…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-14 Amin Aboubrahim , Pran Nath
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