Related papers: Varying Alpha Driven by the Dirac-Born-Infeld Scal…
Using the BSBM varying-alpha theory, with dark matter dominated by magnetic energy, and the spherical collapse model for cosmological structure formation, we have studied the effects of the dark-energy equation of state and the coupling of…
Negative lambda gravitational effective field theories dual to holographic CFTs have potentially realistic cosmological solutions. Generic cosmological solutions of these effective field theories have scalar field evolution that can lead to…
We apply the dynamical systems tools to study the (linear) cosmic dynamics of a Dirac-Born-Infeld-type field trapped in the braneworld. We focus,exclusively, in Randall-Sundrum and in Dvali-Gabadadze-Porrati brane models. We analyze the…
We show by using the method of matched asymptotic expansions that a sufficient condition can be derived which determines when a local experiment will detect the cosmological variation of a scalar field which is driving the spacetime…
It has been argued that a Universe governed by Eddington-Born-Infeld gravity can be compatible with current cosmological constraints. The extra fields introduced in this theory can behave both as dark matter and dark energy, unifying the…
The nature of dark matter and of dark energy which constitute more than $95\%$ of the energy in the Universe remains a great and unresolved question in cosmology. Cold dark matter can be made of an ultralight scalar field dominated by its…
Cosmological constant behavior can be realized as solutions of the Dirac-Born-Infeld (DBI) action within Type IIB string theory and the AdS/CFT correspondence. We derive a family of attractor solutions to the cosmological constant that…
By analysing the cosmological dynamical system with a dark-sector interaction which changes sign during the cosmological evolution, we find a scaling attractor to help to alleviate the cosmic-coincidence problem. This result shows that this…
We develop a framework to study the phase space of a system consisting of a scalar field rolling down an arbitrary potential with varying slope and a background fluid, in a cosmological setting. We give analytical approximate solutions of…
We study the cosmological evolution of a tachyon scalar field T with a Dirac-Born-Infeld type lagrangian and potential V(T) coupled to a canonically normalized scalar field \phi with an arbitrary interaction term B(T,\phi) in the presence…
In this work I discuss the dynamical and thermodynamical equivalence between a general k-essence scalar field cosmology and an arbitrary cosmological model with a decaying vacuum, thus generalizing the approach proposed by Maia and Lima…
An analysis is given of inflation based on a supersymmetric Dirac-Born-Infeld (DBI) action in an axionic landscape. The DBI model we discuss involves a landscape of chiral superfields with one $U(1)$ shift symmetry which is broken by…
We interpret cosmological evolution holographically as a renormalisation group flow in a dual Euclidean field theory, as suggested by the conjectured dS/CFT correspondence. Inflation is described by perturbing around the infra-red fixed…
Friedmann-Lemaitre universes driven by a scalar field, spatially closed and bouncing, were recently studied by Martin and Peter in [1], with the conclusion that the spectrum of their large scale matter perturbations was generically modified…
We consider a single field governed expansion of the universe from a five dimensional (5D) vacuum state. Under an appropiate change of variables the universe can be viewed in a effective manner as expanding in 4D with an effective equation…
We generalize the field theory of global monopole to Dirac-Born-Infeld(DBI) field and investigate the gravitational property of a DBI global monopole in four-dimensional spherically symmetric spacetime. The coupled equations for the metric…
We study the cosmological evolution of two coupled scalar fields with an arbitrary interaction term V_T(\phi,\vp) in the presence of a barotropic fluid, which can be matter or radiation. The force between the barotropic fluid and the scalar…
We study the cosmological evolution of an induced gravity model with a scale symmetry breaking potential for the scalar field. The radiation to matter transition, following inflation and reheating, influences the dynamics of such a field…
We examine the evolution of a closed, homogeneous and anisotropic cosmology subject to a variation of the fine structure 'constant', \alpha, within the context of the theory introduced by Bekenstein, Sandvik, Barrow and Magueijo, which…
It is shown how a Doubly-Special Relativity model can emerge from a quantum cellular automaton description of the evolution of countably many interacting quantum systems. We consider a one-dimensional automaton that spawns the Dirac…