Forever Peace — Joe Haldeman

2043 A.D.: The Ngumi War rages, fought by "soldierboys"--remote control war machines run by soldiers hundreds of miles away. Julian Class is one of these soldiers, and for him, war is indeed hell. The psychological strain of being jacked-in to his soldierboy--and the genocidal results--are becoming too much to bear. Now he and his lover, Dr. Amelia Harding, have made a terrifying scientific discovery that could literally put the universe back to square one. For Julian, however, the discovery isn't terrifying. It's tempting...