Boosted perturbations at the end of inflation (2009)
Zaballa, Ignacio, Sasaki, Misao
We study the effect on the primordial cosmological perturbations of a sharp transition from inflationary to a radiation and matter dominated epoch respectively. We assume that the perturbations are...
Kihara, Hironobu, Nitta, Muneto, Sasaki, Misao, Yoo, Chul-Moon, Zaballa, Ignacio
We study cosmology of the Einstein-Yang-Mills theory in ten dimensions with a quartic term in the Yang-Mills field strength. We obtain analytically a class of cosmological solutions in which the...
Constraints on the primordial curvature perturbation from primordial black holes (2006)
Zaballa, Ignacio, Green, Anne M., Malik, Karim A., Sasaki, Misao
We calculate the constraints on the primordial curvature perturbation at the end of inflation from the present day abundance of Primordial Black Holes (PBHs), as a function of the reheat temperature...
Higher order contributions to the primordial non-gaussianity (2006)
Zaballa, Ignacio, Rodriguez, Yeinzon, Lyth, David H.
In this paper we calculate additional contributions to that part of the non-Gaussianity of the curvature perturbation, which come from the three-point correlator of the field perturbations. We...
Forming sub-horizon black holes at the end of inflation (2005)
Lyth, David. H, Malik, Karim A., Sasaki, Misao, Zaballa, Ignacio
Previous authors have calculated the mass function of primordial black holes only on scales which are well outside the horizon at the end of inflation. Here we extend the calculation to sub-horizon...
A Bound Concerning Primordial Non-Gaussianity (2005)
Lyth, David H., Zaballa, Ignacio
Seery and Lidsey have calculated the three-point correlator of the light scalar fields, a few Hubble times after horizon exit during inflation. Lyth and Rodriguez have calculated the contribution of...