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    Available in PDF - DJVU Format | Dichronauts.pdf | Language: ENGLISH
    Greg Egan(Author)

    Book details

Seth is a surveyor, along with his friend Theo, a leech-like creature running through his skull who tells Seth what lies to his left and right. Theo, in turn, relies on Seth for mobility, and for ordinary vision looking forwards and backwards. Like everyone else in their world, they are symbionts, depending on each other to survive.

In the universe containing Seth's world, light cannot travel in all directions: there is a “dark cone” to the north and south. Seth can only face to the east (or the west, if he tips his head backwards). If he starts to turn to the north or south, his body stretches out across the landscape, and to rotate as far as north-north-east is every bit as impossible as accelerating to the speed of light.

Every living thing in Seth’s world is in a state of perpetual migration as they follow the sun’s shifting orbit and the narrow habitable zone it creates. Cities are being constantly disassembled at one edge and rebuilt at the other, with surveyors mapping safe routes ahead.

But when Seth and Theo join an expedition to the edge of the habitable zone, they discover a terrifying threat: a fissure in the surface of the world, so deep and wide that no one can perceive its limits. As the habitable zone continues to move, the migration will soon be blocked by this unbridgeable void, and the expedition has only one option to save its city from annihilation: descend into the unknown.

"Impressively bizarre . . . Egan may have out-Eganed himself with this one."―Publishers Weekly"Egan (The Arrows of Time, 2014, etc.) specializes in inventing seriously strange worlds; this one might well be his weirdest yet."―Kirkus Reviews"Hard science fiction in its purest form . . . Egan has always done the science half of science fiction as well as anyone can."―The 1000 Year Plan"Per usual for Egan, conceptualizing the math and physics that form the foundation of this bizarre sci-fi tale takes some doing, but the results are well worth the effort."―B&N Sci-Fi and Fantasy Blog“I haven’t been this surprised and entertained by world building for a long time . . . the most brutal and poignant depiction of oppression I have ever seen in fiction. This is why I love Egan’s work – he is absolutely unflinching. . . . Like all of Egan’s work, Dichronauts is brilliant and sweet, heartbreaking and obscure.”―The Kingdoms of Evil“I enjoyed this one very much . . . go and buy the book.”―The Oikofuge“I always enjoy Greg Egan’s writing. Coupled with his scientific background and fertile imagination, he manages to come up with places and aliens unlike any others . . . not only does Egan offer a unique world and alien race – he also provides a cracking adventure story full of tension and excitement right from the start through to the climactic ending. . . . I love this one. Brilliant and inventive, this book reminds me all over again just why I love science fiction so much.”―Brainfluff, 10/10. Reviewed by Sarah J. Higbee

2.5 (8020)
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Supported Devices Windows PC/PocketPC, Mac OS, Linux OS, Apple iPhone/iPod Touch.
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Flowing Text / Pages Pages
Printable? Yes

Book details

  • PDF | 312 pages
  • Greg Egan(Author)
  • Night Shade Books (27 July 2017)
  • English
  • 7
  • Science Fiction & Fantasy

Read online or download a free book: Dichronauts


Review Text

  • By Sam on 31 August 2017

    Got a degree in mathematics or astrophysics or preferably both? No? Then prepare to be confused. I do hold a degree in the latter and I'm not sure I managed to accurately visualise all that transpires in this novel, despite having read the supporting material online (an essential prerequisite to be honest). I enjoyed it more because of the mental challenge than the plot or characters, I think. If you prefer your fiction free from advanced geometry and unusual space-time metrics, then steer clear.

  • By Grant Hutchison on 3 April 2017

    To some extent this is a companion volume to Egan's Orthogonal trilogy. In those books, he imagined what it would be like to live in a universe in which the time dimension behaved geometrically in exactly the same way as the three spatial dimensions, rather than with the hyperbolic coordinate relationship (described by special relativity) that we see in our own universe. In this book, Egan describes a universe in which one of the spatial dimensions has time-like properties - introducing the hyperbolic relationships of relativity into everyday spatial coordinates. (The title, Dichronauts, meaning "travellers in two times" is a reference to the fact that his story universe has two time-like dimensions (time and "axial") and two regular spatial dimensions.So we have a world in which simply trying to rotate an object can change its apparent shape; where it's impossible to rotate a north-facing object to face east, or an east-facing object to face north; where the stable shape for a planet is the hyperboloid depicted on the cover; where light can't travel to the north or south; and where falling over in those directions can have lethal consequences.As with Orthogonal, Egan's aliens have one utterly alien property (in this case, we have two intelligent species that exist as commensals, one threaded through the skull of the other), but otherwise behave and speak like clever and amiable humans. And that's fine, because Egan's imagined world is strange enough without him expecting us to accommodate to an alien society, too. I'm therefore reminded of Hal Clement at his best, though Egan's characters have more humour.The story is a quest, in which the reader finds out more about the world along with the story's characters. There are some surprises, and one toe-curling moment I certainly didn't see coming.I knock off a star only because I think Egan's world may simply be too strange for many readers. In Orthogonal, one could amble along accepting that there was something a little odd about time without fretting about the details. In this story, almost every event is influenced by the strange spatial geometry, and if you don't find the geometry of special relativity engaging, you may be left floundering. Egan provides some explanatory detail in the Afterword (which could productively be read first, since it contains no significant spoilers), and much more information on his website.

  • By Kindle Customer on 10 April 2017

    As with most novels by Egan, I'm very glad I took the time to read it, and equally as glad that I never have to read it again.Egan has a knack for introducing us to genuinely alien worlds and viewpoints, and this novel is no different. Introducing exactly how things differ from our viewpoint is possibly a spoiler, but suffice to say that the afterword explains things extremely clearly... if you can grasp the mathematics.The downside to all this is that the plotting is rather elastic, with no consistent sense of pace, and I couldn't really connect with any of the characters.I feel almost bad rating this at three stars, but it's not a book I can recommend to everyone. In this case, a three star rating means you should pick it up if hard but abstract sci-fi is your thing, or possibly if any of the above has made you curious. Otherwise, I think you'll find it a hard book to enjoy.

  • By Alan on 11 June 2017

    An interesting idea involving a universe with different physical rules. This is explained at the end of the book, it would have been much better at the beginning so the reader could work out what was happening and why.

  • By DrB on 15 August 2017

    Excellent! just thinking about the geometry makes the book worth it.

  • By The stainless steel rat on 5 August 2017

    I really wish Grey Egan would stop writing these thought experiment alternate physics books. They're too much like hard work and are, frankly boring. He is a writer of enormous talent and needs in my opinion to concentrate on narrative and character rather than narrow concept world building.

  • By M. Clare on 5 July 2017

    A terrible book. Some of the scientific concepts in this book are interesting but it is a very slow boring book. Gave up 15% of the way through.

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