In an alien universe where space and time play by different rules, interstellar voyages last longer for the travellers than for those they left behind. After six generations in flight, the inhabitants of the mountain-sized spacecraft the Peerless have used their borrowed time to develop advanced technology that could save their home world from annihilation.
But not every traveller feels allegiance to a world they have never seen, and as tensions mount over the risks of turning the ship around and starting the long voyage home, a new complication arises: the prospect of constructing a messaging system that will give the Peerless news of its own future.
While some of the crew welcome the opportunity to be warned of impending dangers - and perhaps even hear reports of the ship's triumphant return - others are convinced that knowing what lies ahead will be oppressive, and that the system will be abused. Agata longs for a chance to hear a message from the ancestors back on the home world, proving that the sacrifices of the travellers have not been in vain, but her most outspoken rival, Ramiro, fears that the system will undermine every decision the travellers make.
When a vote fails to settle the matter and dissent erupts into violence, Ramiro, Agata and their allies must seek a new way to bring peace to the Peerless - by traveling to a world where time runs in reverse.
THE ARROWS OF TIME is the final volume of the Orthogonal trilogy, bringing a powerful and surprising conclusion to the epic story of the Peerless that began with THE CLOCKWORK ROCKET and THE ETERNAL FLAME.
The conclusion to Egan's trilogy, which follows 2012's The Eternal Flame, is at least as opaque as its confusing predecessors, and appealing only to readers who have managed to wrap their minds around the world building from them. This volume could not be more user-unfriendly for first-timers. Egan buries the series' underlying concept in an afterword; the prose is so dense ("Perhaps a physicist will find a way to transform our positive luxagens into negative ones"), and the hard science so hard, that very few will comprehend either. Apart from the complex physics, the trilogy's plot is not unfamiliar: it is the tale of a desperate attempt to save a world from a cosmic menace, here meteors known as the Hurtlers, by traveling forward in time to benefit from future scientific advances. The debate over the right survival strategy never grips the reader because Egan fails to render his imagined science intelligible the frequent graphs and charts only make things worse.