On the Steel Breeze by Alastair Reynolds

The award-winning author of Blue Remembered Earth continues his saga as the next generation of the Akinya family crosses interstellar space seeking humanity' s future... Chiku Akinya, great granddaughter of the legendary space explorer Eunice and heir to the family empire, is just one among millions on a long one way journey towards a planet they hope to call their new home. For Chiku, the journey is a personal one, undertaken to ensure that the Akinya family achieves its destiny among the stars. The passengers travel in huge self-contained artificial worlds- holoships- putting their faith in a physics they barely understand. Chiku' s ship is called Zanzibar- and over time, she will discover it contains an awesome secret- one which will lead her to question almost every certainty about her voyage, and its ultimate destiny