The Clockwork Rocket

Orthogonal #1

by Greg Egan

In Yalda's universe, light has no universal speed and its creation generates energy.

On Yalda's world, plants make food by emitting their own light into the dark night sky.

As a child Yalda witnesses one of a series of strange meteors, the Hurtlers, that are entering the planetary system at an immense, unprecedented speed. It becomes apparent that her world is in imminent danger — and that the task of dealing with the Hurtlers will require knowledge and technology far beyond anything her civilisation has yet achieved.

Only one solution seems tenable: if a spacecraft can be sent on a journey at sufficiently high speed, its trip will last many generations for those on board, but it will return after just a few years have passed at home. The travellers will have a chance to discover the science their planet urgently needs, and bring it back in time to avert disaster.

Genres: Science Fiction, Fiction, Hard Science Fiction, Steampunk, Space Opera, Fantasy, Space

512 pages, Hardcover

First published June 21, 2011

About the author

Greg Egan specialises in hard science fiction stories with mathematical and quantum ontology themes, including the nature of consciousness. Other themes include genetics, simulated reality, posthumanism, mind transfer, sexuality, artificial intelligence, and the superiority of rational naturalism over religion.

He is a Hugo Award winner (and has been shortlisted for the Hugos three other times), and has also won the John W Campbell Memorial Award for Best Novel. Some of his earlier short stories feature strong elements of supernatural horror, while due to his more popular science fiction he is known within the genre for his tendency to deal with complex and highly technical material (including inventive new physics and epistemology) in an unapologetically thorough manner.

Egan is a famously reclusive author when it comes to public appearances, he doesn't attend science fiction conventions, doesn't sign books and there are no photos available of him on the web.

Excerpted from Wikipedia.

Reviews

[Manny · Rating 4 out of 5]

Don't get me wrong, I loved this book. As several people had told me, there's nothing like it. But at same time, I couldn't help wondering what would happened...

If Tolkien had done linguistics the way Greg Egan does science

"Now what was that?" asked Sam, scratching his head. "Elvish, was it? But it didn't sound like no Elvish I've ever heard. Begging your pardon, sir," he added, turning to face the tall Elf.

"It was Quenya," said Frodo. "Although Quenya and Sindarin have a common origin, they sound very different, because the languages diverged during the long period during the First Age when the two speaker-groups were separated."

"Eh?" said Sam. "I'm sorry Master, but you'll have to say that again. In plain Westron, if you don't mind."

"Let me give you an example," said Frodo patiently. "Take the word elen which I used when I greeted Gildor back in the Shire. Elen síla lúmenn’ omentielvo. A star shines on the hour of our meeting. Now what do you imagine elen means?"

Sam turned red. "Star?" ventured Pippin.

"Exactly!" said Frodo. "If you just think about it, the same root occurs in several other words you know. It's the first two syllables of Elendil. Elenna, 'the land of the star', is one of the many names of Valinor, the Blessed Realm. You have surely heard people refer to Varda as Elentári, 'the lady of the stars'. And in that beautiful song Namárië, which Galadriel sang for us the other day, you will remember her referring to i eleni, 'the stars'--"

"I see!" said Merry. "But why is the plural eleni? I thought Quenya plurals were all formed with suffixes ending in -r. You know, Vala/Valar, mordo/mordor, elda/eldar--"

"You have not been paying attention," said Frodo, his eyes twinkling. "What about the common word Quendi? A plural, is it not?"

"Uh, yes," said Merry, embarrassed at his elementary slip.

"In fact," said Frodo, "the plural in -i is very common in Quenya. It comes directly from Primitive Elvish -î, a word like Quendi representing primitive Kwendî. The plural ending -r arose later. And if you consider the matter a little more carefully, the Sindarin word êl, as for example in elanor--"

"Not wanting to interrupt, sir," said Sam, "but I see a party of orcs headed our way. I can't help thinking we should get moving sharpish. If that's alright. Sir."

"I suppose we have to," said Frodo reluctantly. It was always so much more interesting to discuss philology.

To The Eternal Flame

[Tim Hicks · Rating 4 out of 5]

I have a math degree and I have read a LOT of hard SF - and this might be the hardest hard SF I have ever seen. I'm not sure it would be possible to write something harder except perhaps by throwing in some hive minds and teleportation.

And yet, woven among the charts and brain-busting explanations there really is a plot with some reasonably interesting characters.

If I have learned anything from all my SF reading, it is that there are hardly any books that have a very strong concept AND very strong characterizations. It's perhaps unreasonable to require it; better to have it be a nice surprise if it occurs.

I knew from previous Egans that if he postulates some rules for his universe, they may be outrageous but it won't be because he hasn't thought them through. In fact, my one real beef with this book is that it made me feel stupid. After a while I decided that I could live with that, and then it was OK.

If you have not read previous Egans, I don't think this is a good one to start with. Indeed, if you haven't read much hard SF, you might start with some other authors in the sub-genre before tacking Egan.

[Liviu · Rating 5 out of 5]

This is the perfect sf novel and a clear example why sf is still my favorite genre; besides the strong sfnal content though it is very well written and flows on the page and it has in Yalda one of the best characters in recent memories, with a good supporting cast too.

Shapeshifter (for good reasons explained at the author's site about how molecules look like in the universe he describes) generally (see before) six limbed aliens symmetric in 3D in their "normal" form - so they have eyes both back and front for example - that emit light, sleep in beds dug in the ground to cool down (emitting light generates heat in their universe) though of course the well off in cities have special cooled beds, that reproduce by the mother being divided into four - 2 twin pairs that each generally forms a reproducing couple, though there are the occasional solos like Yalda and the social misfits - while the men are conditioned to take care of the children...

A harsh universe with unstable matter, but also a culture of cities, science, technology, society, books, philosophers, scientists...

The people in this universe are "not us" and in some ways are very strange due to their biology - "being able to fly is like being able to know your mother" is one of the simple proverbs that appear in the book - but they are also "us" in many important ways that matter and this is why this book is both a pitch perfect example of how to imagine aliens that are simply not "costume-ones", but that are similar enough that we understand and care about them...

And not to speak of the main story with the orthogonal stars, the threat to their civilization...

The novel moved me deeply too and I almost cried at the end despite that I saw what will happen from a long time back and I *really, really* want the second installment.

I will have a coherent review in due time since these ramblings really need editing, but for now I am still under the influence of this powerful novel...


FULL FBC Rv HERE:


INTRODUCTION: While contemporary sf is very diverse, encompassing everything from space opera to near-future to alt-history and steampunk, when I think of "pure sf" as the genre has originally evolved to intermix scientific speculation with literature, there are only two authors of today that stand at the top and one of them is Greg Egan whose superb far-future novels like Incandescence, Schild's Ladder or Diaspora combine the cutting edge of today's science with entertaining story-lines. Also Mr. Egan's short stories which are combined in several collections, most notably Luminous, Oceanic, Dark Integers and Crystal Nights and contain some of the most mind-blowing sf at short length that I've ever read, are mileposts of today's genre.

I have read almost all of Mr. Egan's work from the first novels like Permutation City and Quarantine to his prodigious short fiction output with only the two notable exceptions of his near future novels (Teranesia and Zendegi) which are of less interest for me and I never failed to be blown away by his ability to put the most abstract and farthest reaching concepts of modern science in a story that entertains and moves.

So when I read about his planned new series that takes place in a "Riemannian universe", one where the metric - the math concept that encodes the basic physics of the universe - is positive definite and symmetric in space and time as opposed to the indefinite antisymmetric metric in the Einsteinian universe we seemingly inhabit, I was truly intrigued and indeed The Clockwork Rocket was what I expected and more and so far it is my all around top novel of the year for the combination of sense of wonder, great world building, characters and general "human interest" - the shape-shifting, weird biology aliens of The Clockwork Rocket are both strange and familiar and the story of the main character Yalda is as emotional as any I've read this year...

OVERVIEW/ANALYSIS: "The Clockwork Rocket" is the perfect sf novel and a clear example why sf is still my favorite genre; on the one hand there is sense of wonder given by the speculative but informed exploration of an universe with definite though different laws of physics than ours, on the other hand the book flows on the page and it has in Yalda one of the best main characters in recent memories, while the supporting cast is well drawn and distinctive.

The protagonists of the story are strange: the metric of the universe requires complex molecules to be really complex so to speak, so all life is shapeshifting; our heroes are six limbed shapeshifters, symmetric in 3D in their "normal" form - so they have eyes both back and front for example - that emit light, sleep in beds dug in the ground to cool down - though of course the well off in cities have special cooled beds.

They reproduce by the mother being divided into four - two twin pairs, each usually forming a new reproducing couple, though there are the occasional solos like Yalda and the social misfits mostly female, that run away from their twin, not to speak of the usual hardships of life that prevent exponential overpopulation from the generational doubling above, while the longer lived men are conditioned to take care of the children...

A harsh universe with unstable matter, but also a culture of cities, science, technology, society, books, philosophers, scientists... The people in this universe are "not us" and in some ways are very strange due to their biology - "being able to fly is like being able to know your mother" is one of the simple proverbs that appear in the book - but they are also "us" in the ways that matter. So The Clockwork Rocket is a pitch perfect example of how to imagine aliens that are not "costume aliens" ie pseudo-humans with one human characteristic expanded to usually grotesque proportions a la Star Trek species, but that are similar enough that we understand and care about them...

The book follows the "solo" Yalda - ie she "ate" her twin in the womb as the other "normal" children tease her - from a farmer family but who is lucky enough to have a father who appreciates learning and who has promised Yalda's mother to school any of the offspring that shows inclination. So despite being almost twice as big as the normal female - and females are considerably bigger than males here for obvious biological reasons - and not expected to reproduce - ie be quartered in four - in the usual age range due to the lack of a twin mate, so being potentially of huge help on the family farm, Yalda gets to go to school and later is admitted to the university in one of the cities that form the civilization of the planet.

Soon she starts rewriting the physics books by some ingenious experiments, while becoming involved with a group of "liberated" professional females who had learned how to extend their lives and avoid the harsh fate nature destined for them, since even if they do not mate, there is "spontaneous" reproduction and the chances of such increase drastically with age, while the special drug that prevents it, needs to be taken in larger and larger doses...

And then of course comes the main story we read about in the blurb with the orthogonal stars, the threat to Yalda's civilization and the crazy solution she and some of her friends come up with...

So there is discovery, drama, even the stirrings of social change, while in the second part of the book the pace accelerates and the book becomes a true sf classic of people learning to cope with new, challenging and unforeseen circumstances, while Yalda's saga continues towards its clear conclusion. The novel moved me deeply too and I *really* want the second installment to see where the story goes next since there is ample scope for surprises and the author surely did not show his full hand about his exploration of this wonderfully imagined universe.

Overall, The Clockwork Rocket (A++) is the one sf novel I strongly recommend to read if you want to understand why the genre has fascinated so many people for so long. Even if you are confused at the beginning by the seemingly familiar but actually strange people of the book, keep reading since things will start making sense soon and the story is captivating from the first page till the superb but emotional last paragraph...

"When Yalda was almost three years old, she was entrusted with the task of bearing her grandfather into the forest to convalesce.

**************

After squeezing and prodding the old man all over with more hands than most people used in a day, Doctor Livia announced her diagnosis. “You’re suffering from a serious light deficiency. The crops here are virtually monochromatic; your body needs a broader spectrum of illumination.”

[Bradley · Rating 4 out of 5]

Greg Egan writes some freaky cool SF. But a word to the wise: expect relatively rigorous math when you step into his worlds.

I'm not saying that you can't follow any of the plots or enjoy the characters without it, but your basic enjoyment of this will stem directly from your enjoyment of FREAKING COOL MATH.

Not that I followed everything, myself, but learning and enjoying the process gave me pretty much all the enjoyment I needed while reading. :) I mean, yes, getting to know a race of people (read aliens) who are very much plant-like and bud and regrow limbs and eat the light that the forest produces IS FREAKING COOL. And learning that their light perception gives them the ability to grok a much deeper sense of red and blue shifts, even minor time-travel perception, is also FREAKING COOL.

And then we learn that this whole universe happens to be envisioned on a simple little alteration from our own? That there is no light-speed? That the speed is based on the frequency and there is no upper limit, that energy can be created out of very odd sources? Like plants? This isn't energy conservation, this is energy creation. As in, fundamental.

So yeah, we go from basic life to basic science to uncovering the secrets of this particular universe all the way up to making a generational starship run by intelligent plants and see them STOP TIME and ... go backward. :)

And Egan does all of this step by step, giving us a sometimes loose interpretation but still a helluvalot more strenuous proof than almost any SF out there. Besides his own, of course. Because he kinda does this all the time. And blows us away. :)

Otherwise, what we have here is a steampunk novel with plant-aliens breaking the fundamental laws of the universe on a generational starship. HOW COOL IS THAT? :)

[Felicia · Rating 3 out of 5]

Super conflicted about this book. I believe if I could remember more of my college physics I would REALLY love this book. Because the whole premise is that we're on a made-up world with weird aliens whose world is ruled by TOTALLY made-up physics. There is a TON of exposition about how the physics works which made it feel like a pseudo textbook in a way, did you ever read Sophie's World? Kind of like that, but not as accessible. Because in Sophie's World you had the context of understanding more as a basis to build on. This book requires you to understand basic physics in order to understand how it is NOT like that on this world.

I think there should have been a character who was new to the world and needed to be explained to IN COMPARISON to his/her world, that way I could have gotten on board more.

That said, it was an interesting read with an interesting female alien protagonist. Some complex social and political subjects are dealt with very deftly. Not having read other books by this author it definitely makes me want to pick up something else he's written, maybe with less homework involved :)

[Erik · Rating 3 out of 5]

I’m fascinated by the celebrity of painting. Most children leave elementary school able to recognize names like Van Gogh or Da Vinci but are wholly unfamiliar with other names like Faraday, Turing, Laozi, Kant, Saladin, Tolkien, or so on and so forth. Why is that? What is the obsession with Renaissance-era painters to explain this disconnect between their relatively minute historical importance and their fame?

I’m sure I don’t know the answer, but in many ways it mirrors the personal experience of viewing a painting. For the average person, there’s… really not much to it. Of all aesthetic experiences, I believe painting possesses the largest disparity between the creating and viewing experiences. Take even the most famous paintings - Starry Night or the Scream or the Mona Lisa - and how long will your average person linger in front of it at a museum? A minute? Nope. For the Mona Lisa, it’s an average of 15 seconds.

Ultimately, paintings don’t offer much interactivity. They don’t have much content, visual or otherwise. I doubt I’m alone in finding painting museums boring. And yet I can still appreciate these works’ artistic heft, the weight of effort that went into their creation. The artist’s entire life, the thousands of paintings to finally reach masterpiece level.

Those are my feelings, more or less, towards Greg Egan’s Orthogonal Trilogy.

What literally god-like genius must it take to imagine a universe with physics radically different than our own, populate it with a suitable intelligent life, and then chart a course for how that life will discover and manipulate the laws of the universe around them. And Egan does that! It’s got competing theories, political factions pushing their own theories, cross-discipline paradigm shifts as a result of breakthroughs, dead end ideas… and sometimes those dead ends make a comeback to turn out to be the correct theory!

It is genius. I cannot overstate that. It is genius. I’ve read sci-fi with alien species, of course, and alternate dimensions and such. But they have ALWAYS been primarily qualitative, never quantitative to any real degree. Most science fiction is really just futuristic fantasy. Greg Egan puts the science back in science fiction.

BUT - and this is a big BUT - the actual experience of reading the Orthogonal trilogy is awkward and dissatisfying.

At this point, I’ve read almost every novel Egan has written. Except for his out-of-print debut novel, Orthogonal trilogy are my last three. So I know well Egan’s modus operandi.

Basically, he writes science thrillers: a civilization-level catastrophe occurs or looms - vacuum decay in Schild’s Ladder, a quantum rewriting virus in Terenesia, a drought in Dichronauts, etc - and in response, science must save the day! Which essentially means the protagonists must better understand the universe because what is science but the process of understanding?

His early novels - Quarantine in 1992 up to Schild’s Ladder in 2002 - take place in our universe and feature human or post-human protagonists. Incandescence in 2008 bridges his early and later novels, as it is set in our universe and one of the protagonists is post-human BUT the other is quite alien. Then his most recent novels - this Orthogonal trilogy in 2011 and Dichronauts in 2017 - not only feature non-humanoid protagonists… they’re also set in entirely different universes, with different laws of physics!

Orthogonal’s physics change is small but fundamental:

In our universe, in the ‘metric’ of GR’s spacetime, we treat space distances as positive but time distances as negative. If you’ve ever encountered time dilation in your sci-fi or studies, then you know what this negative sign means: travelers moving at extreme speeds will age LESS than those who do NOT take detours through time.

In the Orthogonal universe, time distance is ALSO positive, which means time dilation occurs in the opposite direction: the travelers will age much MORE than those who remain at home. This is, in fact, the core plot, though it takes like half of the first book (which is otherwise rather boring milieu / slice-of-life stuff) to get there:

The (essentially) anti-matter half of the Orthogonal’s universe has looped back around and will soon collide with the normal matter half. In order to avert this cosmic catastrophe, the protagonists launch a generational ship travelling at extreme speeds so that its travelers can improve the state of their science, come up with some way to save the rest of the civilization, and eventually turn around and do so.

So Egan’s standard MO of a science thriller, which I quite enjoy. The problem is that the small alteration of a negative to positive sign in the metric doesn’t just invert time dilation, it changes EVERYTHING. No universal light speed, so stars in the night sky are no longer pinpricks of light but rainbows. And the release of light actually INCREASES energy, so plants/crops now emit light, rather than absorb it. And so on and so forth. It changes so much that I don’t even know what it changes.

For example, I’m almost done with book two at the point of writing this review, and the scientists have just about discovered Pauli’s Exclusion Principle (aka degeneracy pressure) to help explain why gravity doesn’t turn ALL solids into black holes. But I’m like… is PEP even valid anymore? And there wouldn’t really be ‘black holes’ would there? There could be gravity wells that only trap SOME of the colors of light but not others. And… sigh… I really don’t have the time, energy, or expertise to explore a new physics rabbit-hole every other page.

Which breaks the reading experience of a science mystery/thriller.

The way thrillers - and most other genres - work is by generating expectations. Consciously or not, the reader makes guesses about what’s going to happen next and feels compelled to keep reading to discover how those guesses match up with reality. That’s part of what makes humans more intelligent than other animals - our hypothesis engine.

But how can you make expectations when dealing with a universe SO UTTERLY ALIEN to our own? Like HALF of this book is science explanations, but they’re largely opaque even to a science freak like me because I have no idea which assumptions/knowledge I’m allowed to employ in understanding them.

In my Diaspora review, I referenced a strange sadness, in which I considered it one of the greatest sci-fi books I’ve ever read but would recommend it to almost no one. Orthogonal is even worse. This review saddens and disquiets me. The books are an incredible work of genius. Truly, truly genius. But I wouldn’t recommend them to anyone I know, not even myself.

The one optimism I have to cheer me up, though, is the thought that Egan might well go the way of van Gogh: obscure and unappreciated in his own time. But a future, more capable, more enlightened humanity will better able to understand and appreciate his accomplishment. So cheers! Here’s to hoping we overcome our own planetary catastrophe and make it that far.

[Robert · Rating 3 out of 5]

In one sense this is the most ambitious SF novel I've ever read. In every other it's kinda insipid. That one sense? The science! Generally, SF that isn't actually Engineering Fiction or (the very rare) Mathematics Fiction or Alternative History does its science by saying those scientific laws you know? They're approximately right but what if there was this extra thing I've made up? (Hyperspace, wormholes that don't have singularities in the middle, infinite computing power...)

Egan asks, what if the fundamental topology, geometry and laws of relativity were in fact different? (Here's a universe where there's no maximum velocity, time behaves exactly like space, in terms of laws of motion, oh, and the universe is the shape of a ring doughnut.) The answer is, apparently, then your story is 50% exposition about the consequences for physics, chemistry and biology, as discovered by our characters. Said consequences are very weird indeed and require more graphs than I've ever seen in a novel by some stretch. Perhaps the most weird thing, though, is that the consequences for alien psychology and social structure are almost negligable...

I'm pretty excited about reading the two follow-up volumes but mainly because I want to know how microscopic physics works over there in Torus Universe. Whether and how the aiens save their planet come a long distant second and third. I have no idea how this stuff is supposed to appeal to anybody without a physics BSc, I don't know.

[Tudor Ciocarlie · Rating 5 out of 5]

Fabulous book! Greg Egan changed a minus sign with a plus one in the space-time version of Pythagoras's Theorem and created an extraordinarily alternate universe in which interstellar voyages takes longer for the travelers, not less and there is no universal speed limit and no speed of light.

The Clockwork Rocket also has some of the most fascinating aliens characters I've ever encountered - six limbed shapeshifters with frontal and rear eyes, that emit light and reproduce by the mother being divided into 2 pairs of twins (all the explanations for why everything is as it is in this universe are on Greg Egan’s site).

This book has everything: very well written, fascinating universe that makes you think about this one, great characters, super science, good actions and a sequel!

If you are interested to know what happens if you travel through space with infinite speed READ this book!

[Bryan · Rating 2 out of 5]

Clever idea, but too much science and not enough fiction. The whole reason why I read sci-fi is to escape beyond the constraints of the laws of physics. Changing the laws of physics and seeing how this plays out probably will appeal to some people, but to me it felt too much like a physics homework assignment.

[Simona B · Rating 4 out of 5]

A masterclass on how not to coddle your readers, and for this reason one of the bravest and anti-novelistic novels I know.

[Alan Zendell · Rating 2 out of 5]

Greg Egan is an outstanding writer. I wish I could comment as glowingly about The Clockwork Rocket. It simply caused me too much pain to get through.

The characters, their biology, their values, and their exploits are all interesting enough. I suppose that if I'd read the Afterword and the author's blog about the universe he was inventing first, I might have experienced less pain, but a book like this should stand alone. Egan invents his own physics in this book. Now, I have a degree in physics, and this book simply made my head spin. I grant that it's beyond clever to present an entirely made up science using geometry and graphs without equations, but it's a nasty trick to play on readers who aren't aware of the game.

What befuddles me most about this book is trying to imagine who the publishers thought they were marketing it too. If trying to figure it out gave me a headache, what of readers who don't have a background in science? When the very smart people in my writers' group came upon the word "causality" in my novel Wednesday's Child, they shrieked and insisted that I remove it wherever possible. I can't even guess at how they'd react to A Clockwork Rocket.

[Mike · Rating 4 out of 5]

Let’s start with the rating on this one. It was reasonably-written, had some interesting character development and inhabited a universe that was very different from our own. It held my attention pretty well for its 300-odd pages, so it’s at least a solid “3”.

To his credit, the author has invented a “space” (universe if you prefer) where physics, chemistry, and biology are very, very different from our own. In the beginning, the reader is tossed into it without any explanation. As the book progresses the protagonist (and readers) get to “discover” how this special “space” operates. These facts are presented in a kinder, gentler way than say in “The Quantum Thief” (no that’s not a slam, just a comparison).

In this novel, what gets “revealed” is primarily the physics (and cosmology) of the universe. The author lets the characters explain or teach these principles with text and figures. Although nicely presented for the average reader (and crucial to the plot) I wonder if some readers will just gloss over these sections. I hope not. The end of the book has a couple of appendices and an afterword.

While Mr. Egan doesn’t add too much to the material presented within the book, he does give a little background about the 4-dimensional universe and how it differs from our own. For originality I would mark him up another star, but I also think that more of the “supplementary” material might have been added to the back of the book rather than just placed online. So, I’m going to dock him (and his publisher) half of that extra star.

Although a lot of the book is concerned with the people and society (and the inequality of their biology) the “cosmology” and “rocketry” take up the majority of it. This is a more reflective book than a lot of steampunk, but it has common elements. To our eyes, the mechanisms and energy sources that the actors must deal with seem primitive and rudimentary. Their world’s chemistry dictates that they use certain materials in certain ways and only in those ways; but throughout the book there are hints that this is not necessarily so. (I will resist the temptation of giving examples.) I am hoping that in the next novel the rocketeers make discoveries in “chemistry”. I have my suspicions but I want to see how this plays out.

As for the biology of the inhabitants, we learn a fair amount about the sentient species that our protagonist belongs to, but less about the other creatures. I’m not giving anything away by saying that one group is clearly held up as some key issue to be investigated as the books progress.

I enjoyed seeing how the “people” of the world dealt with the practical issues of creating and launching their “rocket”. Yes the title is apt: the steampunk-like mechanisms make this a clockwork system of propulsion. If you only read it for that, then I think you will still be intrigues, but it is and hold the promise of so much more. If you like concepts that are markedly different and not just a coat of fresh paint over our own universe, then this book and series is for you. The author expects you to do some work to follow along and I know that that is not for everyone. (It may be that the online material contains a lot of “easy” explanations for the casual viewer – I don’t know as I haven’t looked, yet.)

I’ve been drifting a bit in this review…. Time to focus on what I thought was the best.

In the timeframe of this one volume, we have the burgeoning science of physics (primarily focused on light – no pun intended) moving from a Newtonian understanding to an Einsteinian one (to put it in our own past history of science). Of course it is not so simple. There are elements of astronomy (akin to the Big Bang) mixed in as well as time and gravitation. But the reader does get a clear view of how a few keen minds uncovered the laws that govern their universe. It’s compressed over a shorter time than our own (say from the late 1870s through the 1920s and 30s), but that is a convenience that keeps the story within one lifetime as well as holding the reader’s attention. It’s not quite the same as sitting next to Albert in the Swiss Patent Office, but it’s pretty good. This restores that half star I took away above!

So, here at the end of the review, I hope that you are interested. Even more, I hope that if you read this you will stay interested and spend a little time working through the optics and space explanations. If you blow through them, you’ll probably still like the book, but you’ll miss out one some of the depth and fun. It’s four (4.0) stars all the way. I’m looking forward to the next volume.

[“Gideon” Dave Newell · Rating 3 out of 5]

This novel follows the familiar formula that Egan fans delight in: an alien hero works out fundamental physics to defend his/her/its species in a race against impending cataclysm from natural forces that are not, initially, well understood. Here, the greatest stylistic twist is that there is no counterpoint perspective from a more familiar human or near-human protagonist, nor indeed, any additional first-person characters. The story is told in a sequence of episodes from the lifetime a single creature, our protagonist Yalda. Her planet and species are never named, being alone in their perceived cosmos, so I’ll call them ‘Orthogonals’ in reference to the unique premise that the story stems from. I can’t do any justice to the carefully described mathematics provided at every step of the hero’s journey, but can summarize by saying that her pocket universe has a different, orthogonal geometry from our own, and Egan has extrapolated this to invent a marvelous and internally consistent set of physics for her to discover along with the reader.

The novel’s theme is also a familiar one: The triumphant of applied science and nobility of those who practice it’s careful pursuit. Egan even pays homage to history’s persecuted and martyred scientists by including a dash of this to the ‘Orthogonal’ civilization he’s created. In his world, however, the selfless scientists manage to escape their adversaries and found a society of their own, where all injustices are banished and the whole community labor together for the common good and a grand project to rescue their planet. Great care is given to the details of each discovery and the particulars of the plot are largely devised in service to this exposition. I feel the story would have been more engaging and the characters more relatable if these narrative priorities could be reversed. I also would have enjoyed more interpersonal conflict and greater moral ambiguity in the characters, who all felt a little too single-minded and one dimensional (no mathematical connotation intended). Yalda particularly, is a bit too righteous, and would have been much more interesting with some dramatic flaw or dark angle. Her one social handicap is an unavoidable accident of nature, completely a faultless situation, that makes her subsequent sufferings at the hands of the unenlightened seem in parallel to historical figures like Alan Turing and other victimized minorities. The story ends with moderate abruptness, although not exactly a cliffhanger, and the largest question tensely unanswered in anticipation of the follow-up novel(s). However on its own, it still stands suitably complete, and will satisfy the reader.

[Jason · Rating 5 out of 5]

4.5 Stars

This is a totally different take on an alien race very much like our own as they struggle with the impending doom that may befall their planet. A crash with an orthongonal star.

The aliens are very different from us. They are practically amorphous and plant like in nature in that they can sprout arms, hands, and other appendages at will. Their morphology is based around their abilities to control their skin... Their reproduction is sexual in nature but can also be asexual in nature as females can spontaneously reproduce if no male is present.

Their unique biology aside, we quickly come to realize that these "People" are very much like you and me and that their dreams and fears are much the same as ours. Their society is similar, their technologies, their problems, and their triumphs.

Yalda is an amazing and truly memorable protagonist. She alone elevates this story and adds the emotional impact to make it stand out. Egan has given us a young "Woman" who is strong, intelligent, and courageous enough to take on society and to not be afraid to step on tradition.

The structure of this book may intimidate some to quickly turn it away. This is a "Science" novel, on par with your college level physics and mathematics class. Much of the novel centers on Yalda and her friends pondering physics, time and space, and working out many equations and calculations. There are countless diagrams to view that explain their theories, and there is even an appendix at the end that tries to tie our Newtonian physics to that of the Orthagonal physics presented in this book.

I loved the physics, the calculations, the theorems, and the deep questions that were trying to be solved. I reread many pages over and over again and found myself going back to diagrams to try and better understand their thought process, and to tie it in with what I know of our world. This part of the book requires an engaged reader, and may not appeal to those that feel this story reads like a text book.

Greg Egan does this story due credit. He spends mass amounts of time describing the math and science of this book to make it real. Ironically by spending a small amount of time describing anything more than the biology of the alien race within this book, he was able to make them real by showing us a lot about their thoughts and feelings. Yalda is remarkable and the science is incredible, I highly recommend this one to science fiction lovers.

[Liedzeit Liedzeit · Rating 3 out of 5]

I had been warned. This is hard science fiction. Maybe I should have tried a different Egan. But I thought I would manage it. I did not.

I was comfortable with the Three-Body Problem. This though is another league. My knowledge of physics is probably above average but this was way beyond me.

I am sure it is an excellent book. It is certainly well written. And I would go so far as to say I would have given it 5 stars easily had I understood, say, 25% of it. Because I am fascinated with the concept of a truly different universe. As it is I understood about 4%. So I should not rate the book at all. But I give it a wishy-washy 3.

[Neil · Rating 4 out of 5]

Well, I’ve read a lot of hard sf, and this is undoubtedly the hardest I’ve ever come upon! The physics in Yalda’s universe differs from our own. And much of the novel is exposition of those differences, with us basically being lectured in this by Yalda. This does include graphs, without which, it would not really possible to understand the new concepts! Don’t expect it to be easy going! But we do learn along with Yalda et al., which is nice. The protagonists are still uncovering things as we go along.

It’s not all physics exposition however! There’s a really exciting voyage taking place! I only wish this was something we could do in our universe too!

There’s also a fair bit on their reproduction, and how the society deals with this.

In conclusion, it’s kinda a niche read. But if you like hard sf, it’s worth giving it a go. You’ll need to know high school level physics and geometry at a miniumum tho.

I think I enjoyed the quantum mechanics stuff the best; e.g. when they started looking into the structure of solids. The sequels will go into this a lot more I expect!

[Outis · Rating 5 out of 5]

How many books can make you shed a tear as well as break a geometrical sweat?

The silly cover has nothing to do with the book.
I'd recommend approaching the first chapters without spoilers (including whatever is printed on the cover, the appendices and of course most reviews).

I used to think of Egan as a master of the short form and had been less impressed by his longer works. As a result, I had been putting off reading this trilogy of fat books which I saw as a kind of concession to commercial concerns (pointlessly drawn-out series seem to sell well no matter how ill-suited the form is to science fiction). Also, I wasn't thrilled by the premise which felt kind of formulaic (within the context of Egan's books that is).
Prompted by Stuart's recent frustration with the admittedly ridiculous word count of Reynolds' most famous series, I resolved to see what Egan had done with the form. Well, instead of effectively expanding a short story and diluting a few good ideas he just came up with more brilliant ones, built a world which wouldn't have fit a much smaller book and wove in a moving epic story... all that in the first volume (I can't speak for the others yet). What's more, the first book ends on a strong note with the organic conclusion of its narrative (imagine that!).
Other than Stapeldon, I don't know any other science fiction author who exercises their imagination so thoroughly as to assemble enough provocative material to sustain a book of that size (if you do, tell me!).
I still think some of Egan's shorts are better but this is a different kind of goodness. It also brings a lot more to the table than Incandescence.

So what's the book about, generally speaking?
Most obviously, it's about fantasy physics. Unlike with some of Egan's other works, that's merely backdrop for much of the book and it seems possible to enjoy it without caring for physics but there are quite a few passages featuring diagrams and devoted to topology, cosmology, thermodynamics, relativistic effects and so forth. It'd be a shame to miss out entierly as that aspect of the worldbuilding is amazing. Other bits of the book may be brilliant but that's what makes it unique.
Reproductive rights also loom large in this book, and are surprisingly relevant to much of the plot (considering the title). The book's angle on the issue is unique on account of the biology of non-anthropomorphic aliens.
There's quite a bit of social commentary on other issues as well and the book repeatedly leans on the moralizing side which might have been grating in a less exotic setting. I guess it would have been grating anyway if Egan wasn't a humanist.
The book deals with lots of other things I don't want to list, starting with shenanigans related to its title. It manages to pack all that thanks to discontinuous storytelling.

- SLIGHT SPOILERS BELOW -

A few notes about what I see as the worst problems of the book will follow. I'll try to keep the spoilers to a minimum but I there's no way around bringing up specifics.

Early in the book, there's quite a bit of excessively mathematical physics. Later on, observational and experimental data come to the rescue, though I couldn't quite suspend disbelief as to how much of the pretty arbitrary (and at one point arguably fallacious) unphysical speculation ended up being confirmed.
Some of this is simply down to Egan being Egan but, going by the afterword, there's also a specific issue that he takes with a famous Tegmark paper (page 19 of the PDF, mildly spoilery) as it pertains to unphysical properties of elliptic partial differential equations (I'm not kidding) and which seems to have gotten wound up too deeply in the plot too early during the book's conception for the issue to be elided (assuming Egan would have been willing to listen to reason in the first place). And so the characters beeline to the author's pet notion with preposterous alacrity and inexplicable enthusiasm.
At more or less the same point in the book, there's a more general explanatory deficit which, besides being annoying in its own right, compounds the problem. To some extent that deficit can be justified by literary choices (such as not using a single equation... even when discussing the wave equation) but I doubt it was fully deliberate. When a class is held for the benefit of the general public, explanations are comprehensive and clear but when the narrator is mulling over a problem or arguing with someone at her level, assumptions and shortcuts abound (as one would expect). Issues often get eludicated later on so readers may treat the more obscure material as clues in a sort of game but backtracking repeatedly when one doesn't interpret something right the first time can get frustrating. That said, the book is written in such a way that any sciencey bits can be skipped by readers willing to admit defeat.
There are also a few details which don't make sense to me even after finishing the book. In the case of the workings of the titular rocket, I'm pinning it on dramatic license (that thing sure is cool!) but when it comes to the dark spot of a certain astronomical phenomenon, well... either I'm obtuse or something isn't obvious to everyone and should have been spelled out. That or there is a worldbuilding inconsistency but how likely is that?

Oh, and that thing Benedetta did... WTF?

[Chris · Rating 2 out of 5]

What if an interesting physics thought experiment were a novel? Well this is that novel. You might think that it would be a pretty boring novel and you would be right.
There are several things about this book that I did not like.
- There are many scenes where someone is doing Science and learning or discovering something where someone will say "So it's just like when !" which is I assume meant to explain physics to the casual reader so they can follow the story and be excited about the cool physics. This most of the time just makes it boring instead.
- Because in this universe time is a space-like dimension and the story is set in an alien civilization the author has helpfully made up new units. Since we as the reader have no experience of this it makes everything needlessly confusing. Example: "Red Towers is more than 8 strolls from here so it will take us 10 lapses or more to travel there."
- Diagrams. If your book needs diagrams of energy potentials maybe just write a paper.
- This is part 1 out of 3. The author has also thrown in societal upheaval around birth control, prejudice, patriarchy and industrial revolution. Perhaps in order to make the setting more interesting, but it takes away focus from the main story
- "Engineering". Everything related to actually building or constructing anything in the real world is waved away, happens off scene and has unrealistic timelines. This ranges from inventing telescopes to constructing a self contained biome inside a spaceship. If I had to guess this was written by a theoretical physicist.

Plot: Ok but meanders
Style: Decent
Setting: Pretty boring
Characters: Two space-like dimensions

[Andrea · Rating 5 out of 5]

Excellent new offering by Egan, backed by a dissertation of " more than 80,000 words of text and over a hundred illustrations. The pages marked “[Extra]” go into considerably more detail than the main exposition, and are targeted at readers who have studied some physics and mathematics at an undergraduate level " that the author has helpfully posted for the gentle reader at http://www.gregegan.net/ORTHOGONAL/OR...

I read enough of the latter to get the gist of the premise underlying this universe, and launched straight into the story. But my curiosity is whetted enough to return to the physics at a later stage.

Some of the physics left me reeling, but a more superficial understanding does not detract from enjoyment of the story, which is large enough in scope, and exotic enough in execution, to satisfy any lover of physics based-space opera. Perhaps at times the mathematical digressions (Egan is transparently passionate about physics!) overwhelmed the narrative, but not enough to deduct a star from the rating.

And I admit that I shed a tear at the ending.

[R Nair · Rating 4 out of 5]

This was hard. Not only in being hard science fiction but also hard to grasp fully even with a passing understanding of special and general relativity.
For those interested in reading this book, here's a link that helped in familiarizing myself with the physics used in here - https://www.gregegan.net/ORTHOGONAL/0...
Have a look at this before buying the book to know whether this is your cup of tea or not.

[Joey-Joey-Jo-Jo · Rating 1 out of 5]

[Ben Landrum · Rating 5 out of 5]

When I was younger, I consumed a lot of youtube content about Star Wars lore, which I always found more interesting and compelling than the stories set within the universe. As a result, I naturally wondered why there weren't fictional universes that existed on their own like an encyclopedia, independent of contemporary narrative. Greg Egan books are the closest thing to this platonic ideal of faceless worldbuilding I've ever encountered.

It's abundantly obvious that the universe of this book, where some fundamental physical symmetries are reversed and the implications extrapolated, is the protagonist. The people in this book are scenery, existing to either entice the easily distracted with concrete (if poorly written) political intrigue, or participate in socratic dialogues about how the setting's physics work. Greg Egan's characters are generally two-dimensional and wooden, but he steps it up to a level that's truly shocking. When one of the protagonist's deeply forgettable friends dies mitosing (the setting's metaphor for leaving the workforce to raise children), the reactions of her closest friends, who live as part of an underground dedicated to preventing exactly this thing from happening, are comically understated. They spend probably less than a page saying "oh well, nothing we can do now but raise the kids" before trucking on to explore more physics.

The robotic main characters are also not helped by the fact that the guy who reads the Greg Egan audiobooks has an annoying cadence, is committed to reading supposedly tender moments with as much emotion as expository rambling, and does voices which are either slightly more nasal than the narration or outlandishly over the top. People wonder if text-to-speech could eventually replace audiobook readers, and I'd say the state of the art has probably already surpassed this guy. I do like to imagine that he was chosen because this is probably how Greg Egan would have read the books, hurrying past all the interpersonal stuff he obviously doesn't care about to talk more about the object of his fixation.

All that being said, this book is awesome. I won't pretend I understand it on more than a superficial level, but his commitment to constructing what at least seems like a rigorous, internally-consistent universe is Tolkien-esque. Also Tolkien-esque, his website contains a short physics textbook diving deeper into the universe, rendered entirely in bare HTML. At 80k words, it's 70% of the length of the Silmarillion, although probably much more richly illustrated:
If it wasn't clear enough that the books exist to justify the year he spent writing the supplementary materials and introduce his ideas to a broader audience, every page opens with the following header:

SPOILER WARNING: This page contains "conceptual spoilers": although it makes no reference to the plot of Orthogonal, it covers scientific matters that are only revealed gradually in the novel.

It's also interesting to note that he refers to 'novel' in the singular, suggesting that just like Tolkien, he wrote one huge book that his publishers had him break up into a trilogy.

If you enjoy high concept science fiction, I recommend reading Egan, although as other reviews have said, this is a bad one to start with. If you've enjoyed Egan previously, I highly recommend this one.

[James · Rating 2 out of 5]

This feels like a throwback to early science fiction, which is a mixed bag of good and bad. Part of the premise of the story is that it takes in a universe that has different physical laws, that's no problem, but the alien protagonist Yalda extensively explains the physics (including illustrations!) throughout the book. This is a shtick that was popular starting with early SF, Campbell used to call stories that contained too much tech and science talk as "Electric Chicken Plucker" stories, this book skates close to that feathery edge. I am a bit of a science nerd, I have several good books on experimental physics, I just feel that the physics would make a better science article.

Another strange bit is how easily they develop the technology to launch a mountain into space, my disbelieve suspension shocks are overloaded, of course there'd be no story without it and why not go big? (Cities in Flight) It does feel a bit like Rocket Ship Galileo with the various tech explanations and our plucky? heroine. I feel that in most cases, less of this is better, don't hand wave, just have the characters act like its real.

The last part, which is pretty good is the aliens, Yalda is part of a strange, protean race of photovores/omnivores that has one flaw, the females die giving birth. There are social issues that arise from this and make sense given that ugly reality. It also makes this story a bit tragic, the ending's not a happy one. A novel book in the tradition of Golden Age SF, a mix of grandeur and failure.

[Simon B · Rating 3 out of 5]

Greg Egan is a kind of genius and I almost feel someone like me reading this novel is a bit like the author casting pearls before swine. In The Clockwork Rocket Egan creates a universe ruled by a completely different physics & biology and populated by characters with an intriguingly alien physiology. It's a stupendous imaginative effort of hard sci-fi, so I feel a slightly ashamed that I found it a slog to get through at times and read it haltingly over a few weeks.

[John · Rating 4 out of 5]

I'd have given it five stars, but the writing is a little stiff. It's very inventive though, and it's fun to learn alternate-universe physics along with the characters in the book.

[Poiq Wuy · Rating 4 out of 5]

Reseña de la trilogía completa, que también incluye [[2013 - The eternal flame - Greg Egan]] y [[2014 - The arrows of time - Greg Egan]].

Como con otros libros de Egan, la literatura en sí misma no tiene nada destacable: personajes poco interesantes con los que cuesta empatizar, tramas estructuralmente anodinas, estilo prosaico. La literatura es solo una herramienta para transmitir sus ocurrencias: y estas son sublimes. Las repaso someramente.

En este caso estamos ante un proyecto colosal: la creación desde la base de un universo con unas leyes físicas completamente distintas a las del nuestro, con todas las consecuencias que ello tiene. No tan distintas, quizá, sino simétricas: en lugar de su espaciotiempo ser una [[variedad de Lorentz]] es una [[variedad de Riemann]], y por tanto toda diferencia entre direcciones espaciales y temporales es meramente dinámica. Además la variedad está acotada: la topología cerrada del universo está obligada para evitar que diverjan las soluciones a la ecuación de onda de los campos. El análogo a nuestras revoluciones científicas desde el s.XVI tienen lugar a lo largo de la serie, pero siempre marcadas por la signatura homogénea de la métrica: comienza con el análogo a la relatividad especial (primer libro), luego la estructura de la materia (mecánica cuántica, segundo libro) y en el tercero se mencionan aspectos de relatividad general. Merece la pena echar un ojo al material suplementario de su página web https://www.gregegan.net/ORTHOGONAL/O...

La idea es tremendamente ambiciosa y está muy bien resuelta. A ello se suma el trabajo sobre paradojas temporales en el tercer libro y la especulación biológica, que si bien no está tan trabajada como la física es también radical.

Ya que no hay una dirección tiempo, cualquier dirección se puede interpretar como tiempo siempre que haya una cierta coherencia entre las velocidades de los objetos de una zona (relativamente bajas unas respecto a otras) y una flecha temporal marcada por el aumento de entropía. Las trayectorias temporales divergen radialmente desde un punto de excepcional baja entropía, el análogo a nuestro [[Big Bang]] y se ramifican y curvan, intersectándose. Lo que motiva la trama es el cruce entre el sistema estelar que habitan los protagonistas y otro sistema ortogonal a este, y que por tanto desde su punto de vista tiene velocidad infinita; un impacto con alguno de los cuerpos estelares destruiría instantáneamente su planeta. Como no se les ocurre ninguna solución deciden lanzar un cohete con científicos que acelere hasta situarse en paralelo a este sistema ortogonal, pudiendo así estudiarlo, avanzar la física y la tecnología durante generaciones y desarrollar alguna solución. El cohete luego dará la vuelta (lo lanzan sin suficiente combustible para ello, pero ya se les ocurrirá algo) y regresará al planeta. Desde el punto de vista del cohete habrán pasado siglos, desde el del planeta unos pocos años (aquí no se entiende por qué no eligen que regrese en lugar de unos años en el futuro unos años en el pasado, ahorrando tiempo).

Sobre las paradojas temporales, podemos clasificarlas en dos tipos. Las que pretenden violar las leyes de la física al plantear un libre albedrío por encima de ellas, y las que son físicamente posibles pero conllevan algo muy poco probable. Del primer caso son las de viajar al pasado y matar a mis abuelos antes de que se conozcan, Egan las resuelve como Gödel (ver:: [[solución a las paradojas de los bucles temporales - causales - Gödel]]): si no es físicamente posible no puede ocurrir, no es una solución a las ecuaciones de los campos en cuatro dimensiones, da igual lo que opine la intuición sobre el libre albedrío. El espaciotiempo es una variedad de cuatro dimensiones, no hay líneas temporales paralelas ni nada similar. Del segundo caso son las de mandar a mi yo del pasado la novela que me hizo famoso para que no tenga que pensarla, le basta con copiar y publicar. En este caso el espaciotiempo es una solución de las ecuaciones fundamentales, pero, ¿quién escribe la novela? Se trata de una aparición de complejidad donde no es físicamente necesario que aparezca, y por tanto algo altamente improbable, como que por fluctuación cuántica aparezca un elefante en mitad de la habitación (ver:: [[solución a las paradojas de los bucles temporales informacionales - Egan]]). Esto tiene implicaciones en la trama del tercer libro que rompen por completo la lógica narrativa tradicional. En primer lugar, aunque no sea tan relevante, es interesante ver que cuando se instala en la nave un sistema que permite mandar mensajes al pasado (a un momento posterior a la instalación) se detienen los avances científicos. Cualquier descubrimiento que se realizara en el futuro sería comunicado por alguien al pasado, y en ese caso en el pasado ya lo sabrían y sería un caso de aparición de complejidad, así que lo que es abrumadoramente más probable es que no haya avances científicos. Lo más original me parece el momento en que descubren que, a partir de cierto instante futuro, no llegan más mensajes hacia el pasado. Deducen dos posibilidades más probables: un meteorito choca con el cohete, destruyéndolo todo y a todos, o hay algún tipo de sabotaje en el sistema de comunicación, posibilidad más benigna. Pero el sabotaje no puede ocurrir sin alguien que realice el sabotaje, así que un grupo clandestino se organiza para realizar el sabotaje, no porque tengan motivaciones políticas o culturales para ello, sino porque *si nadie realiza el sabotaje, necesariamente lo que ocurrirá es el impacto del meteorito*. El futuro ya está escrito, *y los protagonistas ya lo conocen*, eso es lo que resulta un mecanismo narrativo extraño. En la narración tradicional los personajes eligen cual es el evento futuro que quieren que tenga lugar, y después escogen que causas emprender para que ocurra ese efecto. En este caso *el efecto está fijado*, y los protagonistas tienen que elegir de entre todas las causas que producen ese efecto, cual es la que prefieren. Y todo ello siendo conscientes en todo momento de que sus elecciones, igual que los resultados, ya están escritas y nada puede cambiarlas. Hay un vértigo metafísico potente en esta parte de la trilogía.

Es también muy interesante el trabajo que hace sobre las flechas temporales. Distingue dos, la flecha microscópica, dada por la simetría materia-antimateria (ver:: [[teorema CPT]]) y la flecha macroscópica dada por el aumento de la entropía. El el sistema estelar de origen estas están alineadas de una manera y en el sistema ortogonal de la opuesta. Así, cuando el cohete se sitúa paralelo al sistema ortogonal lo hace con la flecha macroscópica alineada: la física que observan transcurre con naturalidad, pero cualquier contacto es letal, pues es contacto entre materia y antimateria. Cuando el cohete da la vuelta ya es posible el contacto, y de hecho descienden en un planeta, pero en este caso la flecha entrópica del planeta es la opuesta a la de los astronautas. Las escenas que pretenden transmitir las consecuencias de esto son desconcertantes, pero, aun siendo caricaturas divulgativas, en cierta medida transmiten bien la idea: los astronautas tienen una restricción de baja entropía pasada, el planeta de baja entropía futura. Desde el punto de vista de los astronautas ocurren cosas como que sus huellas en el planeta ya están cuando llegan a él, y al pisarlas desaparecen. En el cohete traían polvo que será parte del planeta y que se va juntando, amontonando en configuraciones de menor entropía. Todo esto es muy poco preciso, pero las intuiciones que genera apuntan en la dirección adecuada. Es este cruce de flechas macroscópicas lo que posibilita el sistema de comunicación del futuro hacia el pasado.

Por último, mencionaré algo de la biología. No se sabe si los protagonistas son uni o pluricelulares, ni si se puede aplicar el concepto de célula a ellos. Tienen extremidades que pueden extrudir o absorber, y su sistema circulatorio es el mismo que el digestivo (un tracto que se ramifica desde el esófago hasta capilares, que luego se van unificando hasta el recto). Lo más interesante es que la reproducción no es sexual. Hay dos sexos, mujeres, que dan a luz cuatro hijos por una suerte de mitosis, y hombres, que se encargan de cuidar la descendencia que produce su pareja. Los cuatro hijos son dos parejas de hermanos, cada pareja son un hombre y una mujer y, cuando llegue el momento, él cuidará de los hijos de ella. Las mujeres son más corpulentas y aptas para los trabajos físicos. Todo esto no es tan rompedor como en novelas centradas en ello como [[1987 - Lilith_s brood - Xenogenesis - Octavia Butler]] o [[1969 - La mano izquierda de la oscuridad - Ursula K. Le Guin]], pero está interesante. No desarrolla tanto como podría cómo afectan estos géneros a las estructuras culturales y sociales, que son bastante parecidas a las nuestras; después de la física le interesa un poco la biología teórica, pero se nota que sociología, química y otras áreas le dan igual. En cualquier caso al final de la trilogía domina la visión cercana al [[constructivismo de género]] de Egan, también presente en [[1995 - El momento Aleph - Distress - Greg Egan]]: se logra inventar una forma de que las mujeres den a luz sin morir, lo que hace el sexo hombre innecesario. En el futuro solo habrá personas con sexo mujer pero con las características culturales de ambos géneros.

El final es un tanto abrupto, la solución tecnológica que llevan buscando durante toda la saga se resuelve de un plumazo (descubren como convertir el sol en un reactor y llevarse su sistema solar a paseo, esquivando los cuerpos ortogonales). Esto es algo que se agradece: una vez expuestas las ideas especulativas, lo que le ocurra a los personajes, como ha ocurrido desde el principio, no le importa a nadie.

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24 04 28

[Chris · Rating 3 out of 5]

Greg Egan’s The Clockwork Rocket is an incredibly imaginative read. It posits a universe with physics different from our own, and then explores the consequences of those differences, across biology, sociology, mathematics, astronomy and, yes, physics. It’s a revelatory piece of fiction, and an exceptional work of imagination. On the other hand, parts of it feel more like the reader is in a classroom than a novel.

The narrative centres around Yalda; it follows her life from childhood, as one of several daughters in a farm, through her life as an academic, and beyond. But Yalda lives in an environment very different from our own. The most obvious differences are the physical – Yalda’s species are shape shifters, able to generate limbs within themselves, to move their body mass around to perform tasks. Egan manages to make this seem commonplace within the narrative – causing the extraordinary to seem ordinary. By the close of the text, the reader is likely accustomed to addition and subtraction of limbs. But there’s a biological and social exploration here as well – the species reproduces by fission, and as such, each daughter is eliminated in her own act of procreation. Egan uses this as a rather novel way to talk about gender roles in society. Yalda is almost an archetypal strong female protagonist – if not revolutionary, she’s certainly determined, and unlikely to bend under social pressures. There’s some wonderful discussions around contraception and childcare in a universe where every family is a single parent – and layers of subtext around Yalda and her circle, as the women of the species begin to take up roles in society that demand longevity.

So there’s an interesting universe here. My only issue is that the fundamental physics change that the author has made is what underlies that entire universe. Which is excellent – but the infodumps required to bring the reader up to speed are rather intensive. They’re masked in the narrative as part of the process of scientific discovery for the characters – and are, in that sense, entirely narratively appropriate. However, there are quite a lot of diagrams in the text, and many of them have some degree of geometry or velocity calculations in them. What they have to say is legitimately interesting, it’s just a shame that it wasn’t possible to make them a little more digestible, from the point of view of the reader.

The characters are, largely, backgrops against which our protagonist operates. There’s a couple of antagonists, though their threats never feel entirely serious. And there are a great deal more friends and acquaintances of the protagonist, who feel a tad more real; it’s a shame we don’t get to spend more time with them. Yalda, on the other hand, is a well realised character – with her own thoughts, feelings and goals. Some of these goals may feel a bit alien, but most are recognisable enough to inspire empathy in the reader. At any rate, the protagonist feels like a person. A slightly odd person, operating in a world entirely different from our own, but still a character that the reader can make themselves at home with.
From a plot point of view, we’re left following Yalda as she investigates the ‘Hurtlers’, a possibly cataclysmic series of falling stars in her universe. At the same time we follow Yalda’s evolution as an individual, and the shifting social structure in which she is to be found. There’s a lot going on here. Much of it, especially the social aspect and the struggle with the Hurtlers, is quite compelling – aand I found myself quite keen to find out what happened next.

Really, it’s all very clever stuff, and I’m interested to see where Egan takes the next book in the series. It’s a shame that a lot of it is wrapped in some rather esoteric scientific dialogue, but I’m genuinely impressed by the depth and breadth of imagination on display, as well. Is it worth reading? If you have a reasonable tolerance for theoretical or imaginary physics, absolutely. If you want to approach a genuinely different universe, expertly portrayed, then yes. It’s a decent read, either way – just be aware what you’re getting into.

[Kam Yung Soh · Rating 4 out of 5]

An amazing hard SF book from one of the more interesting authors in the field.

While most other authors may be content to just think, "Oh, let's write a story about how the speed of light is different depending on its colour", Egan really goes in-depth by properly considering the consequences of a universe built along a different type of geometry (in this case, Riemannian Geometry), resulting in a universe where the speed of light depends on its frequency, where the generation of energy creates light, etc.

In this story, we follow Yalda, a 'singleton' who wonders about her world, gets an education and helps make a series of discoveries that not only show her (and us) the nature of light and energy in her world, but also to make a discovery: that the 'hurtlers', streaks of light that are appearing more frequently in her sky, are precursors to huge lumps of matter that threaten to destroy her world.

Her only solution is to launch a spaceship. For in Yalda's universe, a ship travelling along the path of the hurtlers and 'orthogonally' to her world would experience time at a much faster rate. Hopefully, fast enough to accelerate discoveries about the hurtlers on the spaceship so that by the time it returns in no time (from her world's perspective), a solution to save the world can be found.

But after the ship launches, additional problems are found that need solutions, or the ship would fail in its mission. These would continue in the second book of the series, "The Eternal Flame".

For those who want to know more about the physics of Yalda's world, Egan has put up a website with more information but it is best to read it after finishing this book so as not to spoil the enjoyment of learning along with Yalda about the nature of her world.

[Clay Kallam · Rating 1 out of 5]

Greg Egan’s “The Clockwork Rocket” (Night Shade Books, $24.99, 328 pages) is about as confusing a book as I have ever read.

First, it is hard science fiction in two ways: one, it’s about science; and two, that science is fiendishly difficult.

To make it worse, Egan doesn’t cut the reader any slack. It’s an alternate universe that operates under different kinds of rules (Riemannian geometry, if that helps) but at the start, Egan assumes we know the physics is different, and not, to name just one other possibility, that the perceptions of the non-human characters are where the difference lies.

But once we start to accept that different colored light moves at different speeds, and that space and time are more similar (I think) in that universe than ours, Egan just keeps pouring on the charts and diagrams, and having his brilliant heroine keep coming up with hugely dramatic discoveries (sort of like Ayla in the long ago “Clan of the Cave Bear,” who undoubtedly would have discovered relativity if given enough time).

There is a plot involving the heroine and various characters, but it’s pretty bloodless and the book ends as most first books of a trilogy tend to do, with not much resolved. Now those readers who are fascinated by rotational physics, geometry and alternate equations for describing the universe will undoubtedly be on board for the next two books in the Orthogonal series. Sadly, I won’t be among them, as I’d rather spend my time beating my head against my keyboard.

[Cassidy · Rating 4 out of 5]

I've been following Egan's work since Axiomatic and the early novels, and I have to say I really like the direction he's going. I remember reading about the insect-like creatures in the cellular automata world in Permutation City, and wondering what things must be like from their perspective. This book starts to fulfill that promise, with a story told from within a different universe with its own entirely unique physics.

The universe he's created seems to exist at a smaller scale than our own, and the delightfully surprising alien biology and physics turn out to make space travel almost as easy as sea travel in our world. The whole story thus takes on aspects of a fable, in stark contrast to the hard-SF epics of his earlier books. But the typical Egan themes of math, physics, feminism and an unapologetic love of science are as present here as ever.

This gets to the story's main weakness: as much as I love science, I get a little tired of stories whose heroes always end up being the Galileos of their world. Reading Egan I often get the feeling that there are only two kinds of people in his worldview: scientists, and the great mass of mundane individuals whose largely unexamined activities exist mainly to support, or threaten, the pursuit of science. For once, I'd love to read a book that genuinely, sensitively explores one of Egan's amazing worlds from the point of view of anyone other than a scientist. There's little room for cultural things like art, music, or literature in the Orthogonal universe. I doubt Egan himself could exist there.