Dr. William Stoeger, S.J. is a Jesuit priest from the California province of the Society of Jesus, and is also an astrophysicist working for the Vatican Observatory. He is based with the Vatican Observatory research group at the University of Arizona in Tucson. He works on the cosmic microwave background radiation, and areas of cosmology dealing with constraining our models of the universe with astronomical data, and he also works on black hole astrophysics, especially the astrophysics of galaxies and quasars, and some quantum field theory. At the same time he is also very interested in the relationship between religion and science, or more precisely, the relationships between theology, science and philosophy. He is an adjunct associate professor of astronomy at the University of Arizona.