What is "dark matter?" This is a question that has preoccupied astrophysicists for many decades. Observations show that 80% of the matter in our universe is in this mysterious, invisible form. In this talk, Dr. Hezaveh discusses how ALMA, the world's most sophisticated radio telescope, is used to observe some of the most distant galaxies of our universe to learn new things about dark matter. On their 12 billion light year journey to us, light rays from these galaxies pass near other galaxies. As this happens, the dark matter halos of the intervening galaxies, large and small, bend their trajectories, causing the images here on the Earth to look distorted, like images in a funhouse mirror.