JackSimile and the Phantom Fury

Jack Hobbes is nobody special. His life is less than exciting. Daily routines rule his existence. Then, on his way to work one morning, he sees a car identical to his own. Being driven by someone identical to him. The first time is enough to make him think he's going crazy. But when it keeps happening, he realizes that he's getting a glimpse of himself in the future. That's pretty cool, until he sees what the future holds.
Will the universe allow him to change his own future, or will he be a helpless victim of time?And what does Albert Einstein have to do with it?