Joe Haldeman "has quietly become one of the most important science fiction writers of our time" (Rocky Mountain News). Now he delivers a provocative novel of a man who stumbles upon the discovery of a lifetime-or many lifetimes. Grad-school dropout Matt Fuller is toiling as a lowly research assistant at MIT when, while measuring subtle quantum forces that relate to time changes in gravity and electromagnetic force, his calibrator turns into a time machine. With a dead-end job and a girlfriend who has left him for another man, Matt has nothing to lose taking a time machine trip himself-or so he thinks.