ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: David Wands (University of Portsmouth)
Title: Primordial density perturbations from inflation
Date (JST): Thu, Feb 25, 2010, 13:30 - 15:00
Place: Seminar Room A
Related File: 230.pdf
Abstract: I will begin by reviewing the notion that the large-scale structure of our universe arises from small-scale quantum fluctuations during a period of inflationary expansion in the very early universe. Much current interest is focussed on how different physical models can lead to non-Gaussian distributions of primordial perturbations. The parameter fNL has become widely used to quantify the non-Gaussianity of the primordial density perturbation due to inflation or alternative models for the origin of structure in the very early universe. The dimensionless parameter fNL is sufficient to describe the primordial bispectrum in models such as the curvaton scenario or ekpyrotic models. However local evolution on super-Hubble scales can produce other forms of non-Gaussianity which may enable us to distinguish observationally between rival models for the origin of structure.
Contact: Mukohyama