Search
Now showing items 1-5 of 5
Dynamical analysis in scalar field cosmology
(APSPhysical Review D, 2015-06-23)
We give a general method to find exact cosmological solutions for scalar-field dark energy in the presence of perfect fluids. We use the existence of invariant transformations for the Wheeler De Witt (WdW) equation. We ...
Local varying-alpha theories
(World Scientific PublishingModern Physics Letters A, 2015-07-20)
In a recent paper, we demonstrated how the simplest model for varying-alpha may be interpreted as the effect of a dielectric material, generalized to be consistent with Lorentz invariance. Unlike normal dielectrics, such ...
Hyperbolic Inflation in the Light of Planck 2015 data
(APSPhysical Review D, 2015-05-18)
Rubano and Barrow have discussed the emergence of a dark energy, with late-time cosmic acceleration arising from a self-interacting homogeneous scalar field with a potential of hyperbolic power type. Here, we study the ...
Singular Inflation
(APSPhysical Review D, 2015-04-08)
We prove that a homogeneous and isotropic universe containing a scalar field with a power-law potential, V(ϕ)=Aϕ^n, with 0<n<1 and A>0 always develops a finite-time singularity at which the Hubble rate and its first ...
New Singularities in Unexpected Places
(World ScientificInternational Journal of Modern Physics D, 2015-09-28)
Spacetime singularities have been discovered which are physically much weaker than those predicted by the classical singularity theorems. Geodesics evolve through them and they only display infinities in the derivatives ...