Taking the Measure of the Universe with CHIME (the Canadian Hydrogen Intensity Mapping Experiment)

Cosmology is the study of the physical universe and the questions being addressed are profound. How old is the universe? How did it begin? Is it finite or infinite? Remarkably, these questions are starting to be answered. Thanks to precise observations from an array of new instrumentation, we know the age of the universe to better than 1%: 13.77 billion years. We know the content of the universe is dominated by dark matter (26%) and dark energy (71%). Ordinary atomic matter makes up only 4.6% of the universe.To the best of our knowledge the universe is infinite, or very large, and it will continue expanding forever, indeed at an ever faster rate due to dark energy. These conclusions are made possible by our ability to detect and characterize cosmic sound waves, called baryon acoustic oscillations (BAO) that long ago propagated in the universe. The BAO places a distinctive imprint on both the cosmic microwave background radiation and the distribution of galaxies that we observe nearby. I will summarize recent measurements and give an overview of a new digital radio telescope being built in Penticton, B.C., called CHIME. CHIME will map roughly 5% of the entire observable universe. Data from CHIME will tightly constrain the expansion history of the universe and the properties of the dark energy causing it.