Excession by Iain M. Banks
Thousands of years ago, the Culture encountered an Outside Context Problem. A perfectly black sphere materialised out of nowhere next to a trillion-year-old sun from another universe. It did nothing and vanished. Now it has returned, and both the Culture and a hostile alien race known as the Affront are desperate to uncover its secrets. Excession was originally published in 1996 and is the fourth novel in Iain M. Banks's Culture series. As with all of the Culture books, it is a stand-alone novel sharing only the same background and setting, with minimal references to the events of other books and no characters crossing over. A plot summary of the novel makes it sound like Banks's version of a 'Big Dumb Object' book, a novel where the characters are presented with an enigmatic alien entity and have to deal with it (similar to Rendezvous with Rama or Ringworld ). However, this isn't really what Excession is about. Instead, the novel operates on several different l...