It's just a novel. Some people confuse his novels for being factual, which is a bit strange.
Yes, there are some facts in there. He's obviously quite knowledgeable about the arts, for example, and he's done his research about the places he describes, and offers little bits of insights about science, such as how the particle collider works.
He then uses his research and spins a fictional story around it. Sometimes he even slightly twists the facts to suit the story. Many authors do this, and it's understandable.
I've never quite understood why some readers think that just because there are
some facts in there, the entire novel must really be the truth, that it's all a conspiracy and the authorities/church are keeping all this from us, and so on, and so forth...
