How much cosmological information can be measured?

Abstract: Cosmologists' work is to measure the modes of fluctuations in the Universe. The total number of modes one can measure depend on the maximum space and the highest value of perturbation modes one can measure. In this talk, I will first discuss how much information that current CMB experiments (e.g. WMAP and Planck satellites) have already measured, and how much improvement future experiments (e.g. galaxy surveys, 21-cm surveys) can make. In addition, I will give a physical picture of how this “measurable information” changes in the past and future, and discuss what is the ultimate measurement precision of the cosmological parameters in the long term future.