Related papers: Cosmological Moduli Dynamics
We study dynamical moduli stabilization driven by gaugino condensation in supergravity. In the presence of background radiation, there exists a region of initial conditions leading to successful stabilization. We point out that most of the…
Compactified string theories give rise to discrete symmetries which are essential if they are to provide a realistic low energy theory. We find that in a class of four dimensional string theories these symmetries are constrained by similar…
High precision cosmological observations in last decade suggest that about 70% of our universe's energy density is in so called "Dark Energy" (DE). Observations show that DE has negative effective pressure and therefore unlike conventional…
We investigate the possibility of obtaining inflationary solutions of the slow roll type from a low energy Lagrangian coming from superstrings. The advantage of such an approach is that in these theories the scalar potential has only one…
We develop the cosmological perturbations formalism in models with a single non-local scalar field originating from the string field theory description of the rolling tachyon dynamics. We construct the equation for the energy density…
In effective supergravity theories following from the superstring, a modulus field can quite naturally set the neccessary initial conditions for successful cosmological inflation to be driven by a hidden sector scalar field. The leading…
The cosmological constant problem can be understood as the failure of the decoupling principle behind effective field theory, so that some quantities in the low-energy theory are extremely sensitive to the high-energy properties. While this…
The low-energy physics of (quasi)degenerate one-dimensional systems is typically understood as the particle-like dynamics of kinks between stable, ordered structures. Such dynamics, we show, becomes highly non-trivial when the ground states…
Scalar weak gravity conjectures (SWGCs) attempt to pinpoint the ranges of couplings consistent with a fundamental theory of all interactions. We identify a generic dynamical consequence of these conjectures for cosmology and show that SWGCs…
Local and global properties of the moduli space of Calabi--Yau type compactifications determine the low energy parameters of the string effective action. We show that the moduli space geometry is entirely encoded in the Picard--Fuchs…
Inflationary cosmology has provided a predictive and phenomenologically very successful scenario for early universe cosmology. Attempts to implement inflation using scalar fields, however, lead to models with serious conceptual problems. I…
We study cosmological consequences of non-constant brane world moduli in five dimensional brane world models with bulk scalars and two boundary branes. We focus on the case where the brane tension is an exponential function of the bulk…
We show that it is possible to combine an early phase of String Gas Cosmology which can explain the origin of the observed structures on cosmological scales with a short later period of power law inflation which creates spatial flatness.…
We explore the cosmological dynamics of a minimalistic yet generic string-inspired model for multifield dark energy. Adopting a supergravity four-dimensional viewpoint, we motivate the model's structure arising from superstring…
In this paper, we show how the generic coupling of moduli to the kinetic energy of ordinary matter fields results in a cosmological mechanism that influences the evolution and stability of moduli. As an example, we reconsider the problem of…
We obtain cosmological constraints on models of inflation which exhibit rapid roll solutions. Rapid roll attractors exist for potentials with large mass terms and are thus of interest for inflationary model building within string theory. We…
These lectures present a brief review of inflationary cosmology, provide an overview of the theory of cosmological perturbations, and then focus on the conceptual problems of the current paradigm of early universe cosmology, thus motivating…
We study the spectrum, couplings and cosmological and astrophysical implications of the moduli fields for the class of Calabi-Yau IIB string compactifications for which moduli stabilisation leads to an exponentially large volume V ~ 10^{15}…
We review that in perturbative string theory, flat, homogeneous and isotropic cosmological evolutions found in no-scale models at the quantum level can enter into "quantum no-scale regimes" (QNSRs). When this is the case, the quantum…
Additional evidence is presented for a recently proposed effective string model, conjectured to hold throughout the parameter space of the basic 5 dimensional, triply charged black holes, which includes the effects of brane excitations, as…