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Related papers: A parametric reconstruction of the deceleration pa…

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Motivated by recent developments in perturbative calculations of the nonlinear evolution of large-scale structure, we present an iterative algorithm to reconstruct the initial conditions in a given volume starting from the dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-01 Marcel Schmittfull , Tobias Baldauf , Matias Zaldarriaga

Despite the significant accomplishments of general relativity, numerous unresolved issues persist in our understanding of the cosmos. One of the most perplexing challenges is the ongoing accelerated expansion of the Universe, which…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-22 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , Amare Abebe

Cosmic acceleration is investigated through a kink-like expression for the deceleration parameter (q). The new parametrization depends on the initial (q_i) and final (q_f) values of q, on the redshift of the transition from deceleration to…

Astrophysics · Physics 2009-06-23 Emille E. O. Ishida , Ribamar R. R. Reis , Alan V. Toribio , Ioav Waga

In the present analysis, we explore a new version of dark energy called Barrow holographic dark energy within the framework modified gravity called $f(Q,T)$ gravity by adopting the simple homogeneous, isotropic, and spatially flat…

General Relativity and Quantum Cosmology · Physics 2024-08-09 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , K Ghaderi

We explore the prospects for using future supernova observations to probe the dark energy. We focus on quintessence, an evolving scalar field that has been suggested as a candidate for the dark energy. After simulating the observations that…

Astrophysics · Physics 2009-11-07 Brian F. Gerke , G. Efstathiou

An important issue in cosmology is reconstructing the effective dark energy equation of state directly from observations. With few physically motivated models, future dark energy studies cannot only be based on constraining a dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Marina Seikel , Chris Clarkson , Mathew Smith

It is described dynamics of a large class of accelerating cosmological models in terms of dynamical systems of the Newtonian type. The evolution of the models is reduced to the motion of a particle in a potential well parameterized by the…

Astrophysics · Physics 2017-09-29 Marek Szydlowski , Aleksandra Kurek

We investigate theoretical and observational aspects of a time-dependent parameterization for the dark energy equation of state (EoS) $w(z)$, which is a well behaved function of the redshift $z$ over the entire cosmological evolution, i.e.,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 E. M. Barboza , J. S. Alcaniz , B. Santos

We study the evidence for dark energy (DE) evolution at low redshift, using baryonic acoustic oscillations (BAOs) from the DESI Early Data Release, Pantheon+ Type Ia supernovae (SNe-Ia), and redshift space distortions (RSDs) to constrain…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-30 Lili Orchard , Víctor H. Cárdenas

We have reanalysed constraints on the equation of state parameter, w_Q = P/rho, of the dark energy, using several cosmological data sets and relaxing the usual constraint w_Q > -1. We find that combining Cosmic Microwave Background, large…

Astrophysics · Physics 2009-11-07 Steen Hannestad , Edvard Mortsell

We use Genetic Algorithms to extract information from several cosmological probes, such as the type Ia supernovae (SnIa), the Baryon Acoustic Oscillations (BAO) and the growth rate of matter perturbations. This is done by implementing a…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-21 Savvas Nesseris , Juan Garcia-Bellido

Large-scale Fourier modes of the cosmic density field are of great value for learning about cosmology because of their well-understood relationship to fluctuations in the early universe. However, cosmic variance generally limits the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Omar Darwish , Simon Foreman , Muntazir M. Abidi , Tobias Baldauf , Blake D. Sherwin , P. Daniel Meerburg

We put forward a pressure-parametric model to study the tiny deviation from cosmological constant(CC) behavior of the dark sector accelerating the expansion of the Universe. Data from cosmic microwave background (CMB) anisotropies, baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Yan-Hong Yao , Xin-He Meng

Peculiar velocities of galaxies and halos can be reconstructed from their spatial distribution alone. This technique is analogous to the baryon acoustic oscillations (BAO) reconstruction, using the continuity equation to connect density and…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-24 Bernardita Ried Guachalla , Emmanuel Schaan , Boryana Hadzhiyska , Simone Ferraro

We reconstruct the expansion history of the Universe using type Ia supernovae (SN Ia) in a manner independent of any cosmological model assumptions. To do so, we implement a non-parametric iterative smoothing method on the Joint Light-curve…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 Hanwool Koo , Arman Shafieloo , Ryan E. Keeley , Benjamin L'Huillier

We study the accelerated expansion of the universe by using the kinematic approach. In this context, we parameterize the deceleration parameter, q(z), in a model independent way. Assuming three simple parameterizations we reconstruct q(z).…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Remya Nair , Sanjay Jhingan , Deepak Jain

This study proposes a novel parametrization approach for the dimensionless Hubble parameter i.e. $E^2(z)=A(z)+\beta (1+\gamma B(z))$ in the context of scalar field dark energy models. The parameterization is characterized by two functions,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-09 M. Koussour , N. Myrzakulov , S. Myrzakulova , D. Sofuoğlu

With a parametric form of the equation of state parameter of dark energy, a quintessence potential has been reconstructed. The potential is found to be a generalization of a double exponential potential. The constraints on the parameters…

General Relativity and Quantum Cosmology · Physics 2016-01-20 Ankan Mukherjee , Narayan Banerjee

One of the main challenges of modern cosmology is to investigate the nature of dark energy in our Universe. The properties of such a component are normally summarised as a perfect fluid with a (potentially) time-dependent equation-of-state…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-19 J. Alberto Vazquez , M. Bridges , M. P. Hobson , A. N. Lasenby

We investigate how strongly late-time inferences about DE dynamics depend on the functional prior used to represent the expansion history. Using identical late-time combinations of CC, DESI BAO measurements, the Pantheon+ SN1a sample, and…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-15 Özgür Akarsu , Maria Caruana , Konstantinos F. Dialektopoulos , Luis A. Escamilla , Emre O. Kahya , Jackson Levi Said