Orthogonal

3 primary works • 4 total works

The Clockwork Rocket

by Greg Egan

Published 1 July 2011

In Yalda's universe, light has mass, no universal speed, and its creation generates energy; on Yalda's world, plants make food by emitting light into the dark night sky. And time is different: an astronaut might measure decades passing while visiting another star, only to return and find that just weeks have elapsed for her friends.

On the farm where she lives, Yalda sees strange meteors that are entering the planetary system at an immense, unprecedented speed - and it soon becomes apparent that more of this ultra-fast material is appearing all the time, putting her world in terrible danger. An entire galaxy is about to collide with their own.

There is one hope: a fleet sent straight towards the approaching galaxy, as fast as possible. Though it will feel like weeks back home, on board, millennia will pass before the collision, time enough to raise new generations, and time enough to find a way to stop the ultra-fast material.

Either way, they have a chance to save everyone back on the home world.

The Eternal Flame

by Greg Egan

Published 26 August 2012

The generation ship the 'Peerless' is suffering from a population explosion, and the only way to reduce the number of children is by drastically limiting the females' food intake, which will trigger a natural response to famine and stop procreation. So population control consists of two barbaric choices: starvation, or suicide. Trying to find a better way, a biologist starts experimenting with animals, and stumbles on a technique that radically alters the reproductive cycle. But while the advantages are obvious, there's a major drawback: while it spares women from their old role - reproduction without hope of survival - it will essentially wipe out an entire sex. Amid the turmoil created by this new possibility, physicists on the ship are working to develop the technology they will need to complete the mission of the 'Peerless'. The people who brought the ship onto its present orthogonal trajectory used up so much fuel that there is no hope of returning -- unless they can use what little remains far more efficiently. One of the expedition's founders dreamed of discovering the Eternal Flame: a way to generate thrust without consuming any fuel at all.
The inhabitants on board the 'Peerless' have some hard choices to make -- and the wrong one could spell extinction for their entire race!

The Arrows of Time

by Greg Egan

Published 17 October 2013

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 Orthogonal Trilogy

by Greg Egan

Published 18 October 2016