Zobrazeno 1 - 10
of 2 547
pro vyhledávání: '"Quintana, J."'
Current and future large-scale structure surveys aim to constrain cosmological parameters with unprecedented precision by analyzing vast amounts of data. This imposes a pressing need to develop fast and accurate methods for computing the matter power
Externí odkaz:
http://arxiv.org/abs/2407.16640
We explore the cosmological dynamics of a minimalistic yet generic string-inspired model for multifield dark energy. Adopting a supergravity four-dimensional viewpoint, we motivate the model's structure arising from superstring compactifications invo
Externí odkaz:
http://arxiv.org/abs/2402.09570
The matter power spectrum $P(k)$ is one of the main quantities connecting observational and theoretical cosmology. Although for a fixed redshift this can be numerically computed very efficiently by Boltzmann solvers, an analytical description is alwa
Externí odkaz:
http://arxiv.org/abs/2307.03643
Within the framework of modified gravity (MG), the quasi-static (QS) and sub-horizon (SH) approximations are widely used in analyses aiming to identify departures from the concordance model at late-times. In general, it is assumed that time derivativ
Externí odkaz:
http://arxiv.org/abs/2303.14251
Autor:
García-Serna, Santiago, Orjuela-Quintana, J. Bayron, Valenzuela-Toledo, César A., Ocampo-Durán, Hernán
Dynamical system theory is a widely used technique in the analysis of cosmological models. Within this framework, the equations describing the dynamics of a model are recast in terms of dimensionless variables, which evolve according to a set of auto
Externí odkaz:
http://arxiv.org/abs/2302.09181
Publikováno v:
Phys. Rev. D 107 (2023) 08, 083520
The linear matter power spectrum $P(k,z)$ connects theory with large scale structure observations in cosmology. Its scale dependence is entirely encoded in the matter transfer function $T(k)$, which can be computed numerically by Boltzmann solvers, a
Externí odkaz:
http://arxiv.org/abs/2211.06393
Publikováno v:
JCAP 08 (2022) 059
We consider scalar-vector-tensor (SVT) theories with second-order equations of motion and tensor propagation speed equivalent to the speed of light. Under the sub-horizon and the quasi-static approximations we find analytical formulae for an effectiv
Externí odkaz:
http://arxiv.org/abs/2206.02895
Publikováno v:
Physics of the Dark Universe, 101575 (2024)
This paper investigates the cosmological dynamics arising from the interaction between a 2-form field and cold dark matter within a Bianchi I background. Employing a dynamical system analysis, we identify two attractors yielding to exponential expans
Externí odkaz:
http://arxiv.org/abs/2202.07546
Publikováno v:
Phys.Dark Univ. 33 (2021) 100857
In this paper, we study the late time cosmology of a non-canonical scalar field ($k$-essence) coupled to a vector field in a Bianchi-I background. Specifically, we study three cases: canonical scalar field (quintessence) with exponential potential as
Externí odkaz:
http://arxiv.org/abs/2106.06432
Autor:
Motoa-Manzano, J., Orjuela-Quintana, J. Bayron, Pereira, Thiago S., Valenzuela-Toledo, César A.
Publikováno v:
Phys. Dark Univ. 32 (2021) 100806
In this paper, we study a triad of inhomogeneous scalar fields, known as "solid", as a source of homogeneous but anisotropic dark energy. By using a dynamical system approach, we find that anisotropic accelerated solutions can be realized as attracto
Externí odkaz:
http://arxiv.org/abs/2012.09946