The Holtzman effect is a fictional scientific phenomenon in the Dune universe created by Frank Herbert, beginning with the 1965 novel Dune. The effect is never explained in detail, but it makes (among other things) defensive force shields and instantaneous space travel possible. According to the Legends of Dune prequel trilogy by Brian Herbert and Kevin J. Anderson (2002–2004), the Holtzman effect is named after the scientist who discovered it, (though for many of its applications, Holtzman in fact takes credit for the mathematical theories of his assistant, Norma Cenva).