Toroidal, nonpropulsive subspace field. Using Kosinski's warp field equations, Ensign Wesley Crusher created such a bubble in 2367. In an accident, Dr. Beverly Crusher was trapped within it, where her thoughts shaped the reality inside the phenomenon. Since her thoughts at that moment were about lost friends, her universe within the bubble began shrinking until she was the only person remaining. Before the bubble collapsed, Dr. Crusher was rescued by the combined efforts of Ensign Crusher and the Traveler.