What novel by James H. Schmitz involves a type of theoretical or fictional entity existing in a dimension beyond our own?
The Witches of Karres: The Witches of Karres is a space opera novel by James H. Schmitz. The Witches of Karres:  It deals with a young space ship captain who finds himself increasingly embroiled in wild adventures involving interdimensional alien invaders, space pirates, and magic power.
i don't know