Laurence van Cott Niven (born April 30, 1938) is an American science fiction author. His best-known work is Ringworld (1970), which received Hugo, Locus, Ditmar, and Nebula awards. His work is primarily hard science fiction, using big science concepts and theoretical physics. It also often includes elements of detective fiction and adventure stories. His fantasy includes the series The Magic Goes Away, rational fantasy dealing with magic as a non-renewable resource.