29 citations · 98 across the 7 of their papers we have counts for
7 papers
Multifractal charactarization as a function of timescale in the light curves with planetary signal observed by the kepler mission
F. J. S. Lima Filho, V. M. B. Ferreira, P. C. F. da Silva Filho +5
Astrophysical data, in the domains of time, involve a wide range of stellar variability phenomena, among them the magnetic activity of the order of a few hours until the signature…
Dissecting kinetically coupled quintessence: phenomenology and observational tests
Elsa M. Teixeira, Bruno J. Barros, Vasco M. C. Ferreira +1
We investigate an interacting dark energy model which allows for the kinetic term of the scalar field to couple to dark matter via a power-law interaction. The model is characteris…
Lagrangian description of cosmic fluids: mapping dark energy into unified dark energy
V. M. C. Ferreira, P. P. Avelino, R. P. L. Azevedo
We investigate the appropriateness of the use of different Lagrangians to describe various components of the cosmic energy budget, discussing the degeneracies between them in the a…
Extended family of generalized Chaplygin gas models
V. M. C. Ferreira, P. P. Avelino
The generalized Chaplygin gas is usually defined as a barotropic perfect fluid with an equation of state , where and are the proper energy density and pressure…
Phantom Domain Walls
P. P. Avelino, V. M. C. Ferreira, J. Menezes +1
We consider a model with two real scalar fields which admits phantom domain wall solutions. We investigate the structure and evolution of these phantom domain walls in an expanding…
Constraining Logotropic Unified Dark Energy Models
V. M. C. Ferreira, P. P. Avelino
A unification of dark matter and dark energy in terms of a logotropic perfect dark fluid has recently been proposed, where deviations with respect to the standard mode…
Constraints on the dark matter sound speed from galactic scales: the cases of the Modified and Extended Chaplygin Gas
P. P. Avelino, V. M. C. Ferreira
We show that the observed rotation curves of spiral galaxies constrain the sound speed of the dark matter to be , where is the speed of light in vacuum. Using…