Constraining inflation

Constraining Inflation with Cosmic Microwave Background Polarization

Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB polarization to constrain parameters relevant for distinguishing among popular models for cosmological inflation, using the MAP and Planck satellite missions as ex...

Constraining SUSY GUTs and Inflation with Cosmology

In the framework of Supersymmetric Grand Unified Theories (SUSY GUTs), the universe undergoes a cascade of symmetry breakings, during which topological defects can be formed. We address the question of the probability of cosmic string formation after a phase of hybrid inflation within a large number of models of SUSY GUTs in agreement with particle and cosmological data. We show that cosmic str...

Constraining hybrid inflation models with WMAP three-year results

We reconsider the original model of quadratic hybrid inflation in light of the WMAP three-year results and study the possibility of obtaining a spectral index of primordial density perturbations, ns, smaller than one from this model. The original hybrid inflation model naturally predicts ns ≥ 1 in the false vacuum dominated regime but it is also possible to have ns < 1 when the quadratic term d...

Constraining Modular Inflation in the MSSM from Giant Q-Ball Formation

We discuss constraints on which flat directions can have large vacuum expectation values (VEVs) after inflation. We show that only flat directions which are not charged under B-L and develop positive pressure due to renormalization group effects can have large VEVs of order MPl. For example, within the MSSM only the HuHd flat direction is found to be viable. This strongly constrains the embeddi...

The Relation Between Inflation and Inflation Uncertainty In Iran