Are the Stars Outtonight — Allison Kohn

Judith dropped out of school where she was studying physics when her parents died in a plane crash. she reads every book on cosmology she can get her hands on and asks her brother, a physicists and his partner endless questions trying to get affirmation for her theory that her parents are alive and living on another planet. One night she meets a man from another universe who takes her on a trip through the stars.