The series centers around an asteroid called the Stone that suddenly appears on the galactic scene and enters orbit around Earth. However, as the NATO scientists who explore the Stone soon discover, the human-built facilities inside the Stone may not have come from their future, but that of an alternate Earth. The libraries in the Stone tell of a nuclear war that has yet to occur in their time, leaving said scientists the task of changing the course of their own future.Oh, and the descendants of humanity are still living in the asteroid, down a corridor in the last chamber that extends beyond the end of the asteroid. And they've been waiting a long time to come back home...Eon should not be confused with the RPG of the same name.
Eon contains examples of:
After the End: With Earth plunged into a nuclear war, the NATO forces on the Stone convince the Soviets to work together to survive. They eventually return to Earth to start caring for the survivors and dissipating the radiation.
Applied Phlebotinum: Patricia has a device that measures the value of Pi. The problem is Pi is a constant - the ratio of the circumference of a circle to its diameter. Unless someone back on earth discovered that Pi isn't a constant (and what an upending of Mathematics THAT would be...), there's no reason for such a device to exist.
Alien Geometries: The circumference/diameter ratio is only a constant in Euclidean geometry. Some seriously warped spacetime is encountered at various points, and variation in the value of that ratio is a valid (if awkward) way of measuring how warped it is.
Bad Future: Patricia thinks the future history books found on the Stone foreshadow possible events in her own Earth’s future.
But Not Too White: Patricia reassures Paul that he is “the first non-Anglo boyfriend” she’s brought home to meet her parents. But her mother later thinks to herself that Paul looks “more Anglo than the others” because of his pale skin.
The Cuckoolander Was Right: There have been reports of people seeing things around The Stone. They've been brushed off as hallucinations brought on by the stress. Some may indeed have been hallucinations, but Olmy and his Frant were scouting around.
Costume Porn: When the rogue appears to Patricia a second time:
"She rolled over and rubbed her eyes. The rogue's appearance had changed; he now seemed to wear baggy pants and a cardigan sweater. His hair was styled in a loose shag, and a watchless fob hung from a belt loop, terminating in a hemline pocket in the sweater. The rogue was in the height of 2005 fashion. She leaned forward in bed and examined his shoes. Huaraches and Japanese tabi socks completed his wardrobe."
Cybernetics Eat Your Soul: After being shot in the head, Mirsky can feel the difference whenever he thinks with the replacement parts of his brain, and considers himself a different person from before.
Death Is Cheap: Axis City citizens are granted two times brought back from the dead, and after that they spend eterity in city memory, a computer network in which people continue to live rich lives in and can still communicate with those who are still corporeal.
Designer Babies: An interesting twist - to make a child, two personalities are copied from the parents and merged in city memory, and the child grows in city memory. When they decide to become corporeal, they are the ones deciding how they want to be designed.
Gender Bender: Axis City citizens can pick whatever gender they want - or none!
Gender Rarity Value: A shortage of women on the Stone after the Death leads to arming said women to protect against rapes.
The Great Politics Mess-Up: In the novel's version of the twenty-first century, the United States enters a nuclear war with the Soviet Union. Also, The Berlin Wall still seems to be up, due to West German personnel on the Stone.
Hive Mind: Sort of. Frants don't have names. When they are near another Frant, they share all memories with them. As a consequence, all Frants end up knowing everything every other Frant knows.
Human Aliens: The Frants, but oddly enough many of the future humans avoid this by having artificially designed bodies.
I Want My Jet Pack: Patricia says the second chamber, “just doesn’t look that much like the future.” She’s somewhat justified in this case, though, since the second chamber architecture was built to resemble twentieth-century earth; technology in other parts of the Stone is more advanced.
Outrun the Fireball: As an offensive weapon, The Jarts open a gate into the heart of a sun. This is bad for The Way, and the Naderites have to escape it.
Power Trio: The Zampolits have Belozersky as Id, Vielgorsky as Ego and Yazykov as Superego.
Ragnarok-Proofing: Axis City does send someone along now and then to check up on things in the city, but when the library's computer is programmed to handle the repair of a man who had half his head shot off on the offchance that medical services doesn't come when it has been summoned - that's some serious contingency programming.
In the second book, Eternity (tropes below) it is pointed out that because they had gotten to the point that technology not only prolonged life but life depended on it, everything was built to last.
The Worlds Within Worlds Trailer has a trope - who knew a frant would be an Adaptational Badass? In the book Patricia meets Olmy and the frant as she steps off a train, and they leave peacefully - no others were present.
Space Amish: Played with in The Naderites. They keep themselves a tech bracket a little beyond the 21st century, but below the Geshels of Axis City.
Starfish Aliens: Of all the species that trade along the Way, only the Naderites and Frants are humanoid. (The Geshels can be, if they choose.)
Throw-Away Country: Subverted when Patricia reads a textbook with an index of all the casualties in her home state of California.
Timey-Wimey Ball: The book doesn't have time travel, it's more alternate universes - the Thistledown was dragged into an alternate universe which was the same but The Death hadn't occurred yet. This doesn't stop some concern about timey-wimey though, as one of the reasons Olmy takes Patricia to Axis City is because she's almost figured out the math behind the inertial dampeners, and it was some papers she hasn't published yet that laid down the theoretical framework for them.
Year Inside, Hour Outside: When humans closed up The Way after opening their first test gates, the Jarts came though the test gates and had plenty of time (relative to the humans) to make themselves at home.
Set Right What Once Went Wrong: The inhabitants of Axis City are the descendants of those who had to crawl up through the rubble after The Death. In this alternate universe, they are helping the survivors dig out and decontaminate the planet.