Tracy Holsclaw, Ujjaini Alam, Bruno Sanso, Herbert Lee, Katrin Heitmann, Salman Habib, David Higdon
01/04/2010 09:00 AM
Applied Mathematics & Statistics
Understanding the origin of the recently discovered accelerated expansion of the Universe poses one of the greatest challenges in physics today. Due to a lack of a fundamental theory to test, major observational efforts are targeted at characterizing the underlying cause. If the cause is a dark energy, the equation of state w and its possible time evolution will hold clues about its origin. In order to exploit the information from ongoing and upcoming observations it is extremely important to develop a robust and accurate econstruction approach with controlled errors for the dark energy equation of state. We introduce a new, nonparametric, direct reconstruction method based on Gaussian process modeling. We apply this method to recent supernova measurements and for the first time reliably reconstruct the continuous history of w out to redshift z=1.5.
