Anomalies in the cosmic microwave background

Abstract:

Over the past century, our understanding of the Universe has grown dramatically. Today, scientists use a model that requires just six key numbers to describe how the Universe evolved. Yet, some big mysteries remain unsolved. In my thesis, I explore two of these mysteries.

The first involves a signal that might be hidden by our movement through the Universe. Since Earth -- and our entire Galaxy -- is moving, the signals we observe are altered, via the Doppler effect. This makes it hard to separate universe-spanning signals from those caused by our motion. I investigate ways to tell them apart.

The second mystery, cosmic birefringence, rotates the light as it moves through the Universe, like light through a crystal. This could only be caused by a new type of field, like gravity or electromagnetism, and is potentially an observable caused by dark matter or dark energy.