Curvaton field and intermediate inflationary universe model

The curvaton in an intermediate inflationary universe model is studied. This study has allowed us to find some interesting constraints on different parameters that appear in the model.Comment: 16 pages, 2 figures, to appear in Physical Review

On regular rotating black holes

The final publication is available at Springer via 10.1007/s10714-016-2166-7Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.Peer ReviewedPostprint (author's final draft