Zobrazeno 1 - 10
of 123
pro vyhledávání: '"Pàramos, J."'
Autor:
Ramos, M. P. L. P., Páramos, J.
Publikováno v:
Phys. Rev. D 96, 104024 (2017)
We generalize the mechanism for gravitational baryogensis in the context of $f(R)$ theories of gravity, including a nonminimal coupling between curvature and matter. In these models, the baryon asymmetry is generated through an effective coupling bet
Externí odkaz:
http://arxiv.org/abs/1709.04442
Autor:
Azevedo, R. P. L., Páramos, J.
In this work a new non-minimally coupled model is presented, where a generic function $f(R)$ of the scalar curvature factors the usual Einstein-Hilbert action functional, motivated by relevant results obtained from similar models. Its cosmological dy
Externí odkaz:
http://arxiv.org/abs/1611.06606
Autor:
Azevedo, R. P. L., Páramos, J.
Publikováno v:
Phys. Rev. D 94, 064036 (2016)
In this work, we use a dynamical system approach to analyse the viability of $f(R,\mathcal{L})$ candidates for dark energy. We compare these with nonminimal coupled $f(R)$ theories and study the solutions for exponential and power-law forms in order
Externí odkaz:
http://arxiv.org/abs/1606.08919
Publikováno v:
Phys. Rev. D 93, 064002 (2016)
We study the possibility that inflation is driven by a massive vector field with SO(3) global symmetry nonminimally coupled to gravity. From an E^3-invariant Robertson-Walker metric we propose an Ansatz for the vector field, allowing us to study the
Externí odkaz:
http://arxiv.org/abs/1511.03520
Publikováno v:
Phys. Rev. D 90, 042004 (2014)
In this paper we present a computation of the thermally generated acceleration of the Cassini probe during its solar conjunction experiment, obtained from a model of the spacecraft. We build a thermal model of the vehicle and perform a Monte Carlo si
Externí odkaz:
http://arxiv.org/abs/1405.1990
Autor:
Páramos, J., Bastos, C.
Publikováno v:
Phys. Rev. D 86, 103007 (2012)
In this work we study the dynamics of gravitational collapse of a homogeneous dust sphere in a model exhibiting a linear non-minimal coupling between matter and curvature. The evolution of the scale factor and the matter density is obtained for diffe
Externí odkaz:
http://arxiv.org/abs/1207.6258
Publikováno v:
Int. J. Mod. Phys. D 21, 1250035 (2012)
We propose the concept of a space mission to probe the so called flyby anomaly, an unexpected velocity change experienced by some deep-space probes using earth gravity assists. The key feature of this proposal is the use of GNSS systems to obtain an
Externí odkaz:
http://arxiv.org/abs/1201.0163
Autor:
Páramos, J.
One of the most interesting and current phenomenological extensions of General Relativity is the so-called $f (R)$ class of theories; a natural generalization of this includes an explicit non-minimal coupling between matter and curvature. The purpose
Externí odkaz:
http://arxiv.org/abs/1111.2740
In the last few years, the so-called flyby anomaly has been widely discussed, but remains still an illusive topic. This is due to the harsh conditions experienced during an Earth flyby as well as due to the limited data available. In this work, we as
Externí odkaz:
http://arxiv.org/abs/1109.2779
Autor:
Páramos, J., Bertolami, O.
The purpose of this study is to describe a perfect fluid matter distribution that leads to a constant curvature region, thanks to the effect of a non-minimal coupling. This distribution exhibits a density profile within the range found in the interst
Externí odkaz:
http://arxiv.org/abs/1107.0225