"At the Core" is an English language science fiction short story by American writer Larry Niven, published in 1966. It is the second in the series of Known Space stories featuring crashlander Beowulf Shaeffer. The short story was originally published in Worlds of If, November 1966, and reprinted in Neutron Star (1968) and Crashlander (1994). The novel Fleet of Worlds is set in the aftermath of the story, from the Puppeteer point of view. The story is retold, from the point of view of Sigmund Ausfaller, in Juggler of Worlds. The events are also referred to in Ringworld. Source: Wikipedia (en)