Observations of nearby galaxies by Edwin Hubble nearly a century ago have taught us that the universe is expanding, and that it must have been much hotter at early times. Observations at radio wavelengths have led to the detection of the cosmic microwave background, radiation left over from this early phase. Precise observations of this radiation have provided us with a snapshot of the universe around the time when the first atoms formed, only a few hundred thousand years after the Big Bang. Rather remarkably, the small fluctuations observed in the cosmic microwave background radiation teach us that their seeds were created when the universe was only fractions of a second old. Professor Flauger will review what we have learned about the early universe and what we may hope to learn in the coming years.
