English
Related papers

Related papers: Late-time acceleration in Higher Dimensional Cosmo…

200 papers

This paper introduces a novel cosmological model aimed at probing the accelerated expansion of the late Universe through a unique parametrization of the deceleration parameter. We aim to constrain key cosmic parameters by integrating recent…

General Relativity and Quantum Cosmology · Physics 2024-08-14 Himanshu Chaudhary , Ujjal Debnath , G. Mustafa , S. K. Maurya , Farruh Atamurotov

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

The results from the Supernova Cosmology Project indicate a relation between cosmic distance and redshift that corresponds to an accelerating Universe, and, as a consequence, the presence of an energy component with negative pressure. This…

Astrophysics · Physics 2007-05-23 Daniel Enstrom , Sverker Fredriksson , Johan Hansson

In this paper, we attempt to explore the possibility of a obtaining a viable emergent universe scenario supported by a type of fluid known as the extended Chaplygin gas, which extends a modification to the equation of state of the well…

General Relativity and Quantum Cosmology · Physics 2025-08-13 Rikpratik Sengupta , Anirban Chanda , B C Paul , M Kalam

We show that there is a correspondence between cosmology from non-extensive thermodynamics and cosmology with fluids of redefined and generalized equation of state. We first establish the correspondence in the case of basic non-extensive…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Shin'ichi Nojiri , Sergei D. Odintsov , Emmanuel N. Saridakis , R. Myrzakulov

In the late 1990s, observations of type Ia supernovae led to the astounding discovery that the universe is expanding at an accelerating rate. The explanation of this anomalous acceleration has been one of the great problems in physics since…

General Physics · Physics 2015-11-09 Wun-Yi Shu

A non-commutative multi-dimensional cosmological model is introduced and used to address the issues of compactification and stabilization of extra dimensions and the cosmological constant problem. We show that in such a scenario these…

High Energy Physics - Theory · Physics 2009-11-11 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

We describe scalar-bimetric theories where the dynamics of the Universe are governed by two separate metrics, each with an Einstein-Hilbert term. In this setting, the baryonic and dark matter components of the Universe couple to metrics…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Philippe Brax , Patrick Valageas

Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas

There is mounting observational evidence that the expansion of our Universe is undergoing a late-time acceleration. Among many proposals to describe this phenomenon, the cosmological constant seems to be the simplest and the most natural…

Astrophysics · Physics 2010-03-19 S. Carneiro , C. Pigozzo , H. A. Borges , J. S. Alcaniz

In this exploratory study, we investigate the bounds on the equation of state of dark matter. Modeling dark matter as a fluid component, we take into account both positive and negative fixed equations of state. Using CMB, supernovae Ia and…

Astrophysics · Physics 2007-05-23 Christian M. Mueller

We investigate late-time cosmology in the context of modified $f(Q,L_m)$ gravity, considering a non-linear model$ f(Q,L_m) = \alpha Q + \beta L_m^n + \lambda$ where, $\alpha$, $\beta$, $\lambda$, and $n$ are some free parameters. The…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan

A precise determination, and comparison, of the epoch of the onset of cosmic acceleration, at redshift z_acc, and of dark energy domination, at z_eq, provides an interesting measure with which to parameterize dark energy models. By…

Astrophysics · Physics 2008-12-18 Alessandro Melchiorri , Luca Pagano , Stefania Pandolfi

The quasi-static solutions of the matter density perturbation in various dark energy models and modified gravity models have been investigated in numerous papers. However, the oscillating solutions in those models have not been investigated…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-18 Jiro Matsumoto

We have studied the inhomogeneous cosmology in Kaluza-Klein spacetime with a positive cosmological constant in a dust dominated era ($p = 0$). Depending on the integration constant we have derived two types of solutions. The dimensional…

General Relativity and Quantum Cosmology · Physics 2025-02-27 D. Panigrahi , S. Chatterjee

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

A simple speed-up cosmology model is proposed to account for the dark energy puzzle. We condense contributions from dark energy and curvature term into one effective parameter in order to reduce parameter degeneracies and to find any…

Astrophysics · Physics 2007-10-10 Xin-He Meng , Meng Su , Zheng Wang

Astronomical observations strongly suggest that our universe is now accelerating and contains a substantial admixture of dark vacuum energy. Using numerical simulations to study this newly consolidated cosmological model (with a constant…

Astrophysics · Physics 2009-11-10 Fred C. Adams , Michael T. Busha , August E. Evrard , Risa H. Wechsler

In this paper we show that a universe dominated by two components, namely domain walls and dissipative dark matter such that the former slowly decays into the latter may drive power law cosmological acceleration consistent with the high…

Astrophysics · Physics 2009-11-10 Sergio del Campo , Ramon Herrera , Diego Pavon