相关论文: Observational Constraints on New Exact Inflationar…
This paper discusses a simple procedure to reconstruct f (R)-gravity models from exact cosmological solutions of the Einstein field equations with a noninteracting classical scalar field-and-radiation background. From the kind of…
We briefly review the arising of an inflationary phase in the Universe evolution in order to discuss an inhomogeneous cosmological solution in presence of a real self interacting scalar field minimally coupled to gravity in the region of a…
We consider warm inflation in the context of holographic cosmology. The weak and the strong dissipative regime are analysed in the slow-roll approximation and within what is known as intermediate inflation. For an appropriate choice of the…
We discuss a model of gravity coupled to a scalar field that admits exact cosmological solutions displaying an inflationary behavior at early times and a power-law expansion at late times.
We investigate the cosmic inflation within a class of the scalar-tensor model with the scalar-dependent non-minimal kinetic couplings. The inflationary dynamical potential will be applied. Using the slow-roll approximation, we compute…
We investigate a particle physics model for cosmic inflation based on the following assumptions: (i) there are at least two complex scalar fields; (ii) the scalar potential is bounded from below and remains perturbative up to the Planck…
The meaning of the inflationary slow-roll approximation is formalised. Comparisons are made between an approach based on the Hamilton-Jacobi equations, governing the evolution of the Hubble parameter, and the usual scenario based on the…
In Randall-Sundrum type braneworld cosmologies, the dynamical equations on the three-brane differ from the general relativity equations by terms that carry the effects of embedding and of the free gravitational field in the five-dimensional…
We investigate the entanglement due to geometric corrections in particle creation during inflation. To do so, we propose a single-field inflationary scenario, nonminimally coupled to the scalar curvature of spacetime. We require particle…
In this article we study closed inflationary universe models using the Gauss-Bonnet Brane. We determine and characterize the existence of a universe with $\Omega > 1$, with an appropriate period of inflation. We have found that this model…
We consider the question of deriving initial conditions for scalar fields in driving both an early and late quintessence phase. The dark energy field presents an unresolved uniformity problem. Further difficulties with initial conditions…
The simplicity of the CMB data, so well described by single-field inflation, raises the question whether there might be an equally simple multi-field realization consistent with the observations. We explore the idea that an approximate…
We investigate an ability of the exponential power-law inflation to be phenomenologically correct model of the early universe. GR scalar cosmology equations we study in Ivanov-Salopek-Bond (or Hamilton-Jacobi like) representation where the…
A scale-invariant universe can have a period of accelerated expansion at early times: inflation. We use a frame-invariant approach to calculate inflationary observables in a scale invariant theory of gravity involving two scalar fields -…
We consider inflation in a universe with a positive cosmological constant and a nonminimally coupled scalar field, in which the field couples both quadratically and quartically to the Ricci scalar. When considered in the Einstein frame and…
Using numerical solutions of the full Einstein field equations coupled to a scalar inflaton field in 3+1 dimensions, we study the conditions under which a universe that is initially expanding, highly inhomogeneous and dominated by gradient…
In this paper, with the presence of swampland conjecture, we use the complex form of a scalar field and investigate the anisotropic constant-roll of an inflationary scenario. Recently, the complex quintessence field has been used to…
We investigate spatially flat isotropic cosmological models which contain a scalar field with an exponential potential and a perfect fluid with a linear equation of state. We include an interaction term, through which the energy of the…
We use a mathematical approach based on the constraints systems in order to reconstruct the equation of state and the inflationary potential for the inflaton field from the observed spectral indices for the density perturbations $n_{s}$ and…
The Friedmann-Robertson-Walker (FRW) cosmology is analyzed with a general potential $\rm V(\phi)$ in the scalar field inflation scenario. The Bohmian approach (a WKB-like formalism) was employed in order to constraint a generic form of…