Abstract We discuss popular models of inflationary and early post-inflationary magnetogenesis present model-independent upper bounds on the strength resulting magnetic fields imposed by considerations weak coupling, back-reaction Schwinger effect.

We study the two field model for reheating based on the scalar inflaton field, φ, and its interaction with another scalar field, χ, through a Lagrangian term 1 2 gχφ,much investigated for parametric resonance or preheating. Attention is particularly on the quantum excitations of the inflaton field and the metric with a smooth transition from quantum to classical stochastic states, and with rehe...

I review various aspects of techniques for reconstructing the potential of the inflaton field from observations, with special emphasis on difficulties which might arise. While my view is that if inflation is to prove viable then most likely it will be one of the simplest models, it is important to consider the impact should we need to move to a more complicated model-building realm.