Here are worlds where entertainment has replaced education, TV has replaced personal interaction, and censorship endangers the lives of those it claims to protect; totally unmanageable cities; as well as interesting twists on insurance, professional sports, state lotteries, unemployment, and crime and punishment.
Vladislav Kuznetsov, a somewhat luckless engineering student from Ohio, is suddenly snatched from his campus to a strange other world. He gradually discovers that he has travelled forwards in time hundreds of years, to a brutal, post apocalyptic world, dominated by the power of the fearsome Honsun lens. His engineering skills make him valuable, but when he discovers that his work has allowed his ruler to wage savage warfare on the surrounding states, he is horrified, and is determined to save this world by destroying the inventor of the lens. But can he, in an ill-equipped low-tech future, find the right target in the past, before war overwhelms them all?
This is as fully detailed future world, with the masses kept in thrall by a particularly nasty application of the last remaining piece of technology -- a Maguffin that also powers the weapons, and the time machine. After a slightly slow start, it rattles along, with multiple third-person viewpoints, with a great impending sense of doom in the future world. The prose, however, has a peculiarly old-fashioned and rather passionless feel; I was initially suspicious that this was an early previously unpublished work, only published in the year of the author's death. But I can find no evidence of this -- and other web-reviewers seem to imply that it is indeed contemporary. (True, at one point it mentions "credit cards", but that could have been a fix-up, and there is nothing else in the modern-day scenes to help place it in time.) The Biggle themes of ordinary decent people fighting to overcome tyranny are well in place.
"Democracy imposed from without is the severest form of tyranny" runs the motto of the Interplanetery Relations Bureau, who's mission it is to bring democracy to all the worlds of the galaxy. So there secret agents work from within to bring about change. But on Kurr revolt is all but impossible. So Officer Forzon invokes the "Rule of One": one technological change per world. But making only the one change isn't as easy as it sounds.