Using the free time thanks to the holidays as it is New Year's day on a lunar calendar, I managed to go through Incandescence, Greg Egan's latest science fiction book. As with most of the other science fiction he has written, it is indeed hardcore science fiction with a special emphasis on the science. I just love it when a story manages to be interesting while staying within the boundaries of plausible laws of physics, and this story is no exception.
The story is actually two stories in one. The story of a human-descended resident of a cosmopolitan society that spans the outer disk of our Milky Way Galaxy who is lured to search for DNA-based life within the center of the galaxy, which is occupied by aloof intelligences that are completely indifferent and unknown to society in the rest of the galaxy, is intertwined with the story of the very life that is being searched for. While the stories are interesting in themselves, what makes the book truly remarkable is that it actually makes the laws of physics an integral part of the plot.
Half the story is about how an entire world must develop the theory of general relativity, Einstein's theory for gravitation, practically from scratch. And it's not just out of scientific curiosity: the fate of their world literally depends on it. For those who do not know much about general relativity, all the exposition of how their theories are developed will be quite interesting. For those who do know, it would be quite interesting to see how general relativity can actually be used in fiction, not to mention the fun in seeing how the theory could have been discovered.
The only real problem I had with the story was that the relation between the two subplots is not quite made clear. They both have the same world as the same subject, and I can guess how one subplot may relate to the other, but it's only a guess. But perhaps connecting the subplots in a specific way, rather than having the readers guess the connection, was not as important as revealing information about the world in terms more familiar to what we know as the residents of a totally alien world try to learn it themselves.