This is a weird book. At some parts, it’s an excellent example of hard sci-fi (at the end of the volume, the author makes an extensive list of which of the ideas he used are true). At other times, the book gets so deep into the hand-wavy mumbo-jumbo techno-babble that it becomes frustrating and almost comical. The book introduces several super-intelligent characters whose job seems to be to babble on for several pages of science-y exposition while the view-point characters say "I don’t understand." over and over.
As the reader, neither did I. And given the way this exposition butts up against the more understandable hard sci-fi elements, it all becomes a bit disconcerting. For a little while, I understand what’s going on. And then I don’t. And then I do, but no one ever really follows up to re-explain the bit I missed.
While all of this is going on, there’s a reasonably serviceable adventure story happening. Still, at the end of it all, it seems that the adventure wasn’t really a part of the plot at all. One of the characters assures us that it was, but they don’t explain why. So that was somewhat dissatisfying.
And then there’s the entirely new species that’s created just for them to wander off without doing much. Also unsatisfying.
And then there’s the end which…well, you know.
So this is an okay book. It has some fun stuff going on. It has some neat sci-fi ideas of both the hard and soft variety. It plays with some interesting questions (though never answers them in a really satisfying way). So, it’s okay.
There are a couple of other books in Baxter’s Manifold series (it’s not REALLY a trilogy since, as Wikipedia notes, "…the books can be read in any order because the series takes place in a multiverse."). I’ll probably read them one day.
But I’m not in a rush to see what happens.