Zobrazeno 1 - 10
of 184
pro vyhledávání: '"Pereira, S. H."'
In this paper we study the effects of torsion of space-time in the expansion of the universe as a candidate to dark energy. The analysis is done by reconstructing the torsion function along cosmic evolution by using observational data of Supernovae t
Externí odkaz:
http://arxiv.org/abs/2402.00844
In the present work, we apply consistency relation tests to several cosmological models, including the flat and non-flat $\Lambda$CDM models, as well as the flat XCDM model. The analysis uses a non-parametric Gaussian Processes method to reconstruct
Externí odkaz:
http://arxiv.org/abs/2311.10703
Publikováno v:
Phys. Rev. D 109, 023514 (2024)
The possibility of an expanding decelerating Universe in the distant future is investigated in the context of a quintessence scalar field cosmology. Such a conceivable evolution is tested against SNe Ia and $H(z)$ cosmic chronometers data, and also t
Externí odkaz:
http://arxiv.org/abs/2302.01946
Publikováno v:
MNRAS 528, 1573 (2024)
By using recent $H(z)$ and SNe Ia data, we reconstruct the evolution of kinematic parameters $H(z)$, $q(z)$, jerk and snap, using a model-independent, non-parametric method, namely, the Gaussian Processes. Throughout the present analysis, we have all
Externí odkaz:
http://arxiv.org/abs/2212.12346
Publikováno v:
Journal of High Energy Physics 2022
The mass dimension one (MDO) fermionic field is built on a complete set of dual-helicity eigenspinors of the charge conjugation operator, which obeys the statistic of Fermi-Dirac. These spinors are a potential candidate for the description of dark ma
Externí odkaz:
http://arxiv.org/abs/2206.13941
Publikováno v:
MNRAS 515, 5981-5992 (2022)
The Co-varying Physical Couplings (CPC) framework is a modified gravity set up assuming Einstein Field Equations wherein the quantities $\{G,c,\Lambda\}$ are promoted to space-time functions. Bianchi identity and the requirement of stress-energy tens
Externí odkaz:
http://arxiv.org/abs/2204.10764
Publikováno v:
Eur. Phys. J. C 82, 821 (2022)
We study a cosmological model with a fermionic field which can be interpreted as a source of dark energy in the universe. Two different approaches were considered, the first one with a massless fermionic field represented by a standard wave-function
Externí odkaz:
http://arxiv.org/abs/2203.04127
Publikováno v:
Eur. Phys. J. C 82, 356 (2022)
A cosmological model in an Einstein-Cartan framework endowed with torsion is studied. For a torsion function assumed to be proportional to Hubble expansion function, namely $\phi=-\alpha H$, the contribution of torsion function as a dark matter compo
Externí odkaz:
http://arxiv.org/abs/2202.01807
Publikováno v:
MNRAS 519, 633-640 (2023)
A minimal model based on the Co-varying Physical Couplings (CPC) framework for gravity is proposed. The CPC framework is based on the assumptions of a metric-compatible four-dimensional Riemannian manifold where a covariantly conserved stress-energy
Externí odkaz:
http://arxiv.org/abs/2202.01371
Publikováno v:
JCAP11(2022)037
Scalar Fields (SF) have emerged as natural candidates for dark energy as quintessential or phantom fields, as they are the main ingredient of inflation theories. Instead of assuming some form for the scalar field potential, however, this work reconst
Externí odkaz:
http://arxiv.org/abs/2112.09722