Greg Egan is the only sci-fi author in my adult life who makes me think "I like this, but I'm not smart enough to really understand it." Feel free to take that as a recommendation either for or against. :)
So far, Incandescence is the toughest of his novels that I've read, and the main world is an extreme and beautiful conception where the ambient forces are all peculiar and the inhabitants are figuring out their cosmology as the novel goes on.
That said, I really could have used more diagrams while I was reading. I only found out after finishing that Egan has a whole bunch of Java applets on his website explaining the experiments that the main characters in the novel carry out, and why they give the results they do.