Exodus : The Archimedes Engine.

In this first installment of a duology by Peter F. Hamilton, Finn has known nothing but the repressive rule of the Celestials, a group of advanced beings ruling the planet of Centauri, though he dreams of the possibility of boundless space beyond his home. When an arkship that was previously thought lost unexpectedly arrives, Finn sees his chance to embrace a greater destiny and become a Traveler - one of a group of brave heroes dedicated to ensu...