Forever Forward TPB

When a brilliant young scientist accidentally launches himself, his evergreen love and three friends into the future with his unproven time machine, they discover a mysterious message from their future selves: THE ONLY WAY BACK IS FORWARD. Now, as they jump 33 years at a time through the rise and fall of humanity, from post-apocalyptic, climate-collapsed landscapes to advanced robot-run empires, will they find the technology to return to the present... or are they doomed to hopelessly time travel forward... forever?