Nesta tese, discutimos três modelos cosmológicos que são baseados direta ou indiretamente em ideias advindas de teoria das cordas. Depois de uma revisão geral de cosmologia em teoria das cordas, um resumo de cosmologia e ...

We study how both the swampland distance conjecture and the Lyth bound affect the parameter space of multi-field models of inflation. A generic feature of multi-field inflation is that the geodesic distance [Delta phi](G) ...

An important unsolved problem that affects practically all attempts to connect string theory to cosmology and phenomenology is how to distinguish effective field theories belonging to the string landscape from those that ...

An extension of the Starobinsky model is proposed. Besides the usual Starobinsky Lagrangian, a term proportional to the derivative of the scalar curvature, del R-mu del R-mu, is considered. The analyzis is done in the ...

We analyse the efficiency of future large scale structure surveys to unveil the presence of scale dependent features in the primordial spectrum –resulting from cosmic inflation– imprinted in the distribution of galaxies. ...

In the scenario of single-field inflation, this field is described in terms of Jacobian elliptic functions. This approach provides, when constrained to particular cases, analytic solutions already known in the past, ...

We propose a simple toy model for quintessential inflation where a complex scalar field described by a Lagrangian with a U(1)(PQ) symmetry spontaneously broken at a high energy scale and explicitly broken by instanton ...