The Accidental Time Machine is a science-fiction novel written by Joe Haldeman and published by Ace Books in 2007. The story follows protagonist Matthew Fuller, a physics research assistant at the Massachusetts Institute of Technology, as he accidentally creates a machine that can only jump ahead in time, by exponentially longer periods each time. Fuller travels to the year 2252 where he finds society has been decimated by war and become a theocracy based on the Second Coming of Jesus which occurred 71 years ago, and to the year 4346 where he finds society is ruled by an artificial intelligence. Fuller is joined by Martha from 2252 and La from 4346 traveling further into the future until they meet other time travelers who are able to send them back in time. The novel explores themes of soc