The Physics & Astronomy Colloquium Series presents Bharat Ratra of Kansas State University discussing "Spatial Curvature, Dark Energy Dynamics, Neither, or Both" on March 29.

Abstract: Observations over the last two and a half decades have persuaded cosmologists that (as yet only indirectly detected) dark energy is by far the main component of the energy budget of the current universe.

I review a few simple dark energy models and compare their predictions to observational data, to derive dark energy model-parameter constraints and to test consistency of different data sets. I conclude with a list of open cosmological questions.