This is the 1990 sequel to Greg Bear's 1985 Eon. Don't even consider reading it stand-alone.
Eon was a very good hard-sf novel, that unfortunately has come to suffer from being written at a time (1985) when nobody knew the Soviet Union was about to go out with a whimper rather than a bang. By the time Eternity was written in 1990, that was known, and Bear downplayed a lot of the Cold War plot events that were already established in the Eon universe. Unfortunately, another paradigm was about to shift as well, and I refer here to inflationary cosmology. There is no longer any question as to whether the universe is decelerating fast enough to eventually re-contract. Evidence found in the 1990s clearly indicates that the expansion of the universe is in fact accelerating, and the universe as we know it will simply gradually dissipate, forever. No end of time. No build-up of intelligent experience/memory to propel through the Big Crunch into the next cycle of the universe. No "Way" at least not as Bear envisioned it in the 1980s. Sadly this writing has become an exercise in out-of-date geopolitics and cosmology.
Aside from that, in terms of plot and characterization, this is not a strong a work as the original Eon. About 30 years have passed since the sundering of the artificial pocket universe known as the Way from the hollowed and inhabited asteroid known as Thistledown, and Earth itself is only partially recovered. The major known characters scattered through spacetime at the end of Eon, and have mostly now aged appropriately to their circumstances. The major plot suspense now is whether there will be the political will to re-open the Way. Bear lovingly explores the world and life setting of each of the characters drawing them very slowly together. I found this to drag on much more than necessary. One high point, however, was the alternate Greek-dominated Earth where Patricia had been stranded, whose point of departure from our own history was back during the reign of Alexander the Great. I would be interested to read a complete novel in that setting.
In the end, though, I found this to be just a tolerable extension of an aging great work.
Eon was a very good hard-sf novel, that unfortunately has come to suffer from being written at a time (1985) when nobody knew the Soviet Union was about to go out with a whimper rather than a bang. By the time Eternity was written in 1990, that was known, and Bear downplayed a lot of the Cold War plot events that were already established in the Eon universe. Unfortunately, another paradigm was about to shift as well, and I refer here to inflationary cosmology. There is no longer any question as to whether the universe is decelerating fast enough to eventually re-contract. Evidence found in the 1990s clearly indicates that the expansion of the universe is in fact accelerating, and the universe as we know it will simply gradually dissipate, forever. No end of time. No build-up of intelligent experience/memory to propel through the Big Crunch into the next cycle of the universe. No "Way" at least not as Bear envisioned it in the 1980s. Sadly this writing has become an exercise in out-of-date geopolitics and cosmology.
Aside from that, in terms of plot and characterization, this is not a strong a work as the original Eon. About 30 years have passed since the sundering of the artificial pocket universe known as the Way from the hollowed and inhabited asteroid known as Thistledown, and Earth itself is only partially recovered. The major known characters scattered through spacetime at the end of Eon, and have mostly now aged appropriately to their circumstances. The major plot suspense now is whether there will be the political will to re-open the Way. Bear lovingly explores the world and life setting of each of the characters drawing them very slowly together. I found this to drag on much more than necessary. One high point, however, was the alternate Greek-dominated Earth where Patricia had been stranded, whose point of departure from our own history was back during the reign of Alexander the Great. I would be interested to read a complete novel in that setting.
In the end, though, I found this to be just a tolerable extension of an aging great work.