The biggest mistake when reading Adam Roberts is when you approach him like your usual science fiction writer. This, I admit, seems sensible on the surface, since most of his fiction has a SFnal cover that make it look like one. This would be no problem if he were merely writing action adventures, as is the fortitude of so many other writers, but he likes to think about big stuff, big ideas and so on. Which might make him look like your typical hard SF writer, only that he prefers to think about big philosophical question without really thinking the science through.
In most cases, when it comes to the scientific underpinnings of his stories, it’s all just technobabble. Now, even someone like Greg Egan, the grand master of hard SF, has some very speculative content in his books, but there’s always the attempt to make it at least consistent with the rest of what we know, to make it fit to some degree with our present level of understanding.
The biggest problem with Anticopernicus is that it posits intelligence exists all over the universe only in singular form, with one exception. Earth with it’s overwhelming abundance of intelligent life has become the center of the universe due to the massive amount of minds observing the universe (Roberts uses quantum magic to explain this, name-dropping the observer effect, which shows that he really doesn’t understand or care about the underlying principles). Now, apart from the whole overuse of quantum everything in science fiction, one thing that really bugged me was how singular intelligences arose on other worlds. I can only assume that they popped fully formed into existence.
That said, some of the most outrageous ideas have been the basis for some of the best science fiction books. Lets just assume the universe in Anticopernicus works somehow. Even then Anticoperinucs fails to some degree, as Roberts doesn’t do anything more interesting with his premise. There’s no in-depth speculation about what it means to life in an universe where each civilization consists just of one member/person/being, how an accumulation of minds can warp the universe to some degree and so. Roberts just takes his premise, as outrageous as it is, and then does nothing with it apart from showing an extremely self-contained main character who re-discovers his humanity to some degree and thus the worth of life (like thousand if similar tales).
As negative as all this sounds, I still think it was worth the read, especially since I really like reading about gonzo ideas. It’s just annoying that Roberts built such a conventional tale around such an unusual idea. If you have the balls to posit an universe where Earth is really the center of the universe, then you should do something equally interesting with the plot.