Lecture presented at Augustana College, Department of Physics and Astronomy
on the occasion of inducting new members into the local chapter of Sigma Pi Sigma.

 

Seventy percent of the universe is a form of energy never detected on Earth: dark energy. What is dark energy? How do we know it exists?  Answers to these questions lead to a third question, one of the most fascinating in physics today: How is dark energy connected to and explained by fundamental physics?  Answering this question may lead to a radical revision of our notions of space and time.