Saturday, October 15, 2011
170 & 182 Dennison Building
Speaker: Jeffrey McMahon (UM Physics)The `Big Bang' model posits that our universe expanded and cooled from a hotter more dense state in the past. This model is now amply supported by data from a variety of observations, yet a number of questions remain. What were the initial conditions for the state of our universe at the 'beginning' of this expansion? What is in our universe at present and how does it influence the expansion? We have models (called inflation and dark energy, respectively) that seem to answer these questions. In both cases many of the details of these models remain uncertain. New measurements are needed to confirm these models and illuminate the details. In this talk, Professor McMahon will provide an overview of the state of our understanding of the universe and describe new instruments (in the South Pole and Chile) that will make improved measurements of the radiation left over from the Big Bang (called the cosmic microwave background) to help answer these questions.