SUPERNOVAE, DARK ENERGY, AND THE ACCELERATING UNIVERSE: THE STATUS OF THE COSMOLOGICAL PARAMETERS

Abstract

I was asked to present the status of the cosmological parameters, and in particular the status of the recent results concerning the accelerating universe—and the possible cosmological constant or dark energy that is responsible for the universe’s acceleration. This result comes most directly from the recent type Ia supernova work, so although I will mention a few of the approaches to the cosmological parameters, I will emphasize the work with the type Ia supernovae. I will try to give you a sense of exactly how we reached the current conclusions and what the current level of confidence is in that conclusion. Because this presentation will be emphasizing the supernova work, I would like to highlight the strong team of scientists in our Supernova Cosmology Project [1, 2]; you will probably recognize some of the particle physics heritage of this particular team. I also would like to list the names of the members of the other supernova team, led by Brian Schmidt of the Australian National University, that has been working in this field [3]. These two groups together comprise a good fraction of the entire community of scientists working on supernovae.