The standard model of cosmology rests on precision measurements of the cosmic microwave background (CMB) and the distributions of galaxies. It is based on an expanding homogeneous and isotropic universe model, with inhomogeneities that grow due to gravitational instability and give rise to the observed large-scale structures (LSS). The evolution of small inhomogeneities is described by cosmological perturbation theory. Most work to date has been devoted to the study of linearize perturbations. Beyond linear order, there remain many important problems. One of the most important issues is to understand the statistical distribution of perturbations. At linear order, perturbations derived from vacuum fluctuations in the early universe obey Gaussian statistics. However, non-linearities, either in the generation of perturbations or in their evolution, imply deviation from Gaussianity. At the moment we live an exciting time where observations are reaching the precision at which we might rule out a large class of models. Recently, some researchers have reported evidence of non-Gaussianity from CMB, which has triggered massive interest in this field. In the coming years, the Planck satellite will measure non-Gaussianity of CMB anisotropies to a great accuracy. Also it has been suggested that LSS observations can put constraints on primordial non-Gaussianity of density fluctuations to the same accuracy as CMB observations.

This workshop is the second in a series of molecule-type workshops on non-linear cosmological perturbations. The first workshop held at Yukawa Institute during 13-24 April 2008 was very successful covering a wide range of topics related to non-linear cosmological perturbations. This time, we focus more on non-Gaussianity of cosmological perturbations. We aim to systematically predict non-Gaussianity of primordial fluctuations in many possible theoretical models and seek optimal ways to constrain and distinguish between the theoretical models from observations.

The first week of the workshop (15 - 19 March) is devoted to specialized discussions among invited participants. In the second week (24 - 28 March), we would like to widely open this valuable opportunity to all researchers who are interested in this topic. Hence those who participate in this workshop during 24 - 28 March at their own expenses are very welcome, although we may need to restrict the number of participants because of the limitation of the capacity of Yukawa Institute. Due to limited funding availability, we cannot financially support participants except for the invited participants. There will be a three day meeting during the workshop (24 - 26 March) which is open to any researchers and it provides opportunities for participants of the workshop to present talks. Hence, those who wish to participate in this workshop, please send us the application form to the e-mail address below.

This workshop is held as one of the YIPQS molecule workshop series. This workshop is supported by Yukawa International Program for Quark-Hadron Science. This workshop is co-sponsored by the Royal Society International Joint Project grant ``non-linear cosmological perturbations'' between the Institute of Cosmology and Gravitation, University of Portsmouth and YITP, and the Monbukagakusho Grant-in-aid No. 21244033 "Nonlinear, non-perturbative gravitational phenomena in cosmology".

Invited Participants include David Wands (Portsmouth), David Langlois (APC), Andrei Frolov (Simon Fraser U.), Daniel Steer (U. Paris 7), Marco Pelso (U. Minnesota), Eiichiro Komatsu (U. Texas)