-->"There are times when it's worth putting aside the endless myopic navel-gazing that occupies so much literature, in order to look out at the universe itself and value it for what it is."
--->--[[http://www.keepingthedoor.com/greg-egan-the-big-interview/ Interview with Renai Lemay]]

An Australian author who puts the Hard Science back into [[MohsScaleOfScienceFictionHardness Hard Science Fiction]]. Likes to [[ShownTheirWork show his work.]] Quite unapologetic for being deeply technical - he's got his niche of the "1% that treats science as something of interest in its own right", the rest have enough authors writing for them already.

A lot of Egan's early stories first appeared in ''Magazine/{{Interzone}}'' magazine, which can thus boast that he's to some extent their discovery.

!! Works with a page on this Wiki:
* ''Literature/{{Diaspora}}''
* ''Literature/{{Orthogonal}}'' - Aliens in a universe with very strange physics build a GenerationShip in an attempt to avert disaster. A trilogy, consisting of:
** ''The Clockwork Rocket''
** ''The Eternal Flame''
** ''The Arrows of Time''
* ''Literature/PermutationCity''
* ''Literature/{{Quarantine}}''
* ''Literature/SchildsLadder''

!! His other works include:
* ''Distress'' - Political intrigue surrounding the development of a Theory of Everything.
* ''Incandescence'' - Pre-industrial aliens discover General Relativity because their world circles the black hole at the centre of the galaxy.
* ''Teranesia'' - Through quantum computing, life becomes capable of mutating into the optimum form for its environment.
* ''Zendegi'' - Simulations of human neural maps are used to add realism to a virtual world.

Common themes in his works include TheSingularity, [[{{Transhuman}} Transhumanism]], atheism, regional politics, religion being the source of many problems, and non-standard sexual identities.
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!! Tropes in his other works include:
* AdaptiveAbility: In ''Teranesia'', an evolving organism is apparently able to anticipate future challenges and develop appropriately.
* AFormYouAreComfortableWith: In works featuring the galaxy-spanning superculture known as the Amalgam (short stories "Riding the Crocodile" and "Glory", and the novel ''Literature/{{Incandescence}}''), the Amalgam has mastered the trick of manipulating matter on an atomic level to turn pretty much any matter into pretty much whatever they want. The Amalgam's favored method of making FirstContact with young races is to use artificial bodies that mimic the members of the race being contacted. The trope features most prominently in "Glory".
* AllThereInTheManual: He stuffs his stories with heady physics that is almost impossible to fully convey without diagrams and calculus. He has interactive animated simulations on his website for the confused yet still interested. He's recently taken this UpToEleven, posting ''eighty thousand words'' along with ''hundreds of illustrative diagrams'' to describe the alternate-universe physics he invented for ''Orthogonal''.
* AlternateUniverseReedRichardsIsAwesome: "Oracle" is set in a world that diverged from ours around the early twentieth century, with a man named Robert Stoney being born in place of Alan Turing, who nevertheless enters the exact same field, and has the same sexual orientation. Because he was gay in a rather unenlightened time, he is treated about as badly as Turing was in RealLife, except that instead of being castrated and then killing himself, Stoney is subjected to what would have to have been considered CruelAndUnusualPunishment even by the standards of the time, but this is what allows a time-traveler from the future to rescue him, and tell him about future technology. It is this future knowledge that Stoney exploits to come up with such things as an imager that is more effective than X-rays, but provides no risk of cancer, genetically modified crops that have a much higher yield than anything known, sustainable energy, and even ''the beginnings of strong A.I.'' (though Stoney admits that he isn't at that stage yet.)
* AlternativeNumberSystem: Numbers in Egan's works are always shown in decimal thanks to a TranslationConvention, but in several of his works that take place from a nonhuman perspective, it's strongly implied that the characters use a different number base. In ''Literature/{{Orthogonal}}'', the unnamed race of aliens apparently use a duodecimal/dozenal (base-12) number system, while the six-legged "Arkdwellers" in ''Literature/{{Incandescence}}'' clearly use a base-6 system. The clearest evidence of this is that where a human might hyperbolize a large number as "a thousand" or "ten thousand" (ten times a hundred or a hundred times a hundred, respectively), the Arkdwellers tend to use phrases such as "six times thirty-six" or "thirty-six times thirty-six" when they want to exaggerate with an indeterminate large number.
* AuthorAvatar: Martin, the protagonist of "Oceanic" is quite clearly a stand-in for Egan himself, as the story of Martin losing his faith in the local CrystalDragonJesus religion is almost identical to [[http://gregegan.customer.netspace.net.au/ESSAYS/BAB/BAB.html the autobiographical essay]] wherein Egan recounts his own such experience.
* AwesomenessByAnalysis: In "[[http://www.infinityplus.co.uk/stories/tap.htm TAP]]", the users with the highest level of skill with the eponymous AppliedPhlebotinum have this ability, being able to critically analyse everything perfectly. [[spoiler:This is the reason that the villains want to suppress it, as if the ability were widespread, nobody would allow corrupt politicians or religious figures to remain in power.]]
* CallASmeerpARabbit: ''The Clockwork Rocket'' takes place in a universe with entirely different laws of physics from our own. It still uses common words like "plant", "forest", and "wheat" to describe the things that are roughly analogous (never mind that plants gain energy by ''emitting'' light rather than absorbing it).
* CrapsackOnlyByComparison: "Oceanic" gives us Covenant, which the narrative goes to great lengths to set up as a BadFuture in which society has declined, but which doesn't really seem that worse than 21st-century Earth. Of course, when the civilization that preceded it was one in which nobody ever died, it's a bit easier to accept that Martin wishes he were born earlier, especially since then [[spoiler:he wouldn't have lost his mother]].
* CreepyChild: Jane Remedios, of "TAP", gives off this vibe, because she appears to have the emotional maturity of an adult, in a child's body. [[CreepyGood She's one of the good guys, though.]]
* CureYourGays:
** In ''[[http://gregegan.html.customer.netspace.net.au/MISC/ORACLE/Oracle.html Oracle]]'', an alternate universe Alan Turing is locked in a punishingly cramped [[{{Anvilicious}} cage]] by the secret service in an attempt to cure him of his homosexuality. The NoCelebritiesWereHarmed version of Turing notices the Anviliciousness of the situation:
-->Quint was silent for a moment, then he replied with a tone of thoughtful sympathy. "It's unnatural, isn't it? Living like this: bent over, twisted, day after day. Living in an unnatural way is always going to harm you. I'm glad you can finally see that."
-->Robert was tired; it took several seconds for the meaning to sink in. ''It was that crude, that obvious?'' They'd locked him in this cage, for all this time ... as a kind of ham-fisted ''metaphor'' for his crimes?
** His short story "Cocoon" also has the eponymous treatment for pregnant women that [[MoneyDearBoy semi-inadvertently]] prevents gay-making hormones from reaching the baby.
* DespotismJustifiesTheMeans: In "TAP", it turns out that the murder victim's death was caused by [[spoiler:a secret cabal who wish to suppress the TAP technology so that their power is never threatened by a generation of perfect critical thinkers]]. The murder itself is just a means to that end.
* DoesThisRemindYouOfAnything: The main conflict of "Glory" is [[UsefulNotes/ColdWar between two factions of an alien species, which don't trust each other at all and spend most of their time trying to one-up the other at the expense of the planet's smaller countries]], and despite their posturing to the contrary, [[NotSoDifferent neither side has the moral high ground]]. The [[OutgrownSuchSillySuperstitions human main character]] monologues about [[AuthorFilibuster how irrational the whole thing is]].
* DyingDream: An unusual version of this is found in the story "Transition Dreams". A man's brain is scanned and transferred to a computer. The end result is an exact copy, as though the man's mind had been instantaneously transferred from brain to computer. But the mind is conscious of the transfer, and realizes that all its dreamlike experiences of the process must be annihilated before it can be identical to the original brain scan. The real twist, though, is that the end of the story [[spoiler:calls into question whether he even really ''is'' being transferred to a computer, or if he's just plain dying and the whole brain-scan thing is a hallucination born of denial]].
* EvilReactionary: Present occasionally, though subverted in "Oracle". Jack Hamilton's EstablishingCharacterMoment is taking pride at the fact that a LoonyFan of his fantasy novel appears to [[DaydreamBeliever actually believe the setting is real]], instead of being appalled at the FanDumb like any sane author would be, because he considers the book to teach children about the importance of blind faith. He also makes arguments against "materialism" that are quite transparently full of logical holes, is convinced that [[ScienceHero Robert Stoney]] is a Satanist even after Stoney gives him almost undeniable proof of the contrary, and believes that [[ScienceIsBad science itself is of the Devil]]. However, as the story goes on, we find out that he is being brought to despair over his wife's terminal disease, and by the end, he comes off as pitiable, rather than TheScrappy.
* FallenStatesOfAmerica: "In the Ruins" is set here, with American scientists being forced to debase themselves by being called "[[BigStupidDooDooHead poopy-heads]]" and American university students jumping at the chance to study abroad, because the American scientific and technological infrastructure has collapsed. One character outright states that the United States used to actually understand the scientific process, and wasn't always in the sorry state it currently finds itself in.
* FirstContact: Quite a few of Egan's works prominently feature the idea of a spacefaring race making contact with one that hasn't yet attained space travel, and a few, bizarrely, don't even involve space travel at all. A surprising number of them play the trope from the perspective of the spacefaring race.
** ''Literature/{{Diaspora}}'', "Glory", and ''Literature/{{Incandescence}}'' all feature spacefaring humans making first contact with aliens who haven't attained space travel, although in the first case the aliens in question have already met ''other'' spacefaring aliens.
** ''Literature/PermutationCity'' and "Crystal Nights" feature humans who create computer-simulated universes in which life "evolves" from first principles, and the humans make "first contact" with the aliens from literally ''outside'' their known universe (imagine realizing that our entire universe was being simulated--not manipulated, but simply run on a computer--and then imagine meeting the beings who ''designed the computer'').
** "Luminous" and its sequel "Dark Integers" feature humans making first contact with a race of intelligent beings who live in a universe that exists alongside ours--not a parallel universe, exactly, but one that exists in the same space and time. The two universes follow different mathematics, and once each race realizes that the other exists, they are able to communicate more or less by ''doing math'' at each other. [[MindScrew Yeah]].
* FlingALightIntoTheFuture: A species doomed to extinction by a [[spoiler:black hole crashing through their starsystem]] in ''Incandescence'' takes a radical approach to Fling A Light Into The Future: [[spoiler:they engineer a de-novo descendant species and culture able to live within chunks of rock orbiting inside the accretion disk]].
* GeniusDitz: "In the Ruins" has Emma, who, despite being a textbook DumbBlonde, actually knows how to solve some pretty advanced physics word problems, at least when she actually goes through the effort to do so. That's pretty impressive for someone who isn't a physics or engineering major and has no interest in science at all.
* GivingRadioToTheRomans: Played straight in "Oracle", albeit with the twist that the past time that the time traveler improves is no more distant that 1950s Britain. However, since the time traveler is implied to be from pretty far in the future, the native she helps out manages to invent technology that is incredibly advanced even by twenty-first century standards.
* HitlersTimeTravelExemptionAct: {{Justified}} in "Oracle"; the people of Helen's time desperately want to prevent the atrocities of the totalitarian dictatorships of the twentieth century, but are currently unable to do so, as the nature of their time-travel-enabling AppliedPhlebotinum means that any change to an event of that magnitude would affect all timelines which had a UsefulNotes/SecondWorldWar, thereby causing a TemporalParadox. Helen does say though, that the researchers from her time are trying to figure out a way to avoid this problem, suggesting that the situation is not permanent.
* KarmicTwistEnding: "The Moral Virologist" subverts this trope. The MadScientist who created the SyntheticPlague is convinced that [[TheScourgeOfGod he is doing God's will]], but once he is told that he made a miscalculation and his virus is also killing innocent babies, he has a VillainousBSOD. He contemplates turning himself in, so that the world will have the knowledge to cure the virus, and it looks like he will get his comeuppance. But then, [[spoiler:he decides that that would undo all of his plans to force people to conform to fundamentalist morality, and instead chooses the least-effective method of warning people about the virus's effects possible,]] thereby changing the story to a ShootTheShaggyDog.
* LivingForeverIsAwesome: A recurring theme, with "Border Guards" having a CharacterFilibuster against people who believe otherwise.
* MeaningfulName:
** In "Oceanic", the very thinly veiled [[CrystalDragonJesus Jesus stand-in]] is named Beatrice. The name happens to be derived from the Latin word for "blessed".
** "Oracle" features a CaptainErsatz of Creator/CSLewis as the main antagonist, and alludes to [[DifferentWorldDifferentMovies his fictional works]], with the [[Literature/TheChroniclesOfNarnia Narnia]] counterpart being called "Nescia", which is most likely derived from "nescience", that is to say, willful ignorance. "Oracle" is anything but subtle.
* MundaneMadeAwesome: "Glory" opens with a [[TechnologyPorn loving description]] of the process required to transport the human main characters to the aliens' star system, which involves [[JustForFun/AbusingTheKardashevScaleForFunAndProfit creating a kilogram each of matter and antimatter just to explode them in the core of a star, using the resultant energy to shoot two nanomachines to an icy moon several planets away from the aliens' home world, and then build both the heroes' spaceships and their new bodies (which look just like those of the aliens) individually, atom by atom, from the surrounding materials]].
* NoCelebritiesWereHarmed: In "Oracle", any historical figure who would be important to the plot gets replaced, though less important figures are name-dropped without alteration. Specifically, Robert Stoney replaces Alan Turing, and Jack Hamilton replaces C. S. Lewis. At least in Stoney's case, there is some FridgeBrilliance about it, since [[spoiler:Helen couldn't save Turing himself, because it would quite possibly negate her timeline, but a CaptainErsatz of him is perfectly fine]].
* ObliviouslyEvil: When they aren't straight up Evil Reactionaries, his villains tend to be people who honestly do not comprehend that their worldview is self-contradictory and harmful to society as a whole. Jack Hamilton of "Oracle" and Prospero of "The Planck Dive" are probably the best examples (though calling the latter one "evil" is a stretch).
* ReligionIsWrong: Having future humans having OutgrownSuchSillySuperstitions is typical of Egan's ''oeuvre'', but only in "Oceanic" does he set up a wholly fictional religion, which the characters discover to be entirely wrong.
* SaveBothWorlds: [[spoiler:What Helen's ultimate goal is implied to be]] in "Oracle", by getting people to combine with AlternateUniverse versions of themselves, in an attempt to produce an optimal time line. A GainaxEnding ensues.
* SchizoTech: "The Moral Virologist" is set in the year 2000, yet is about a religious fanatic engineering a virus that would kill much of the world's population, all by himself. Fortunately, people are nowhere close to creating synthetic viruses in RealLife even at the current time, let alone all the way back in 2000.
* TheCuckoolanderWasRight: "TAP" opens with Helen Sharpe being convinced that her mother was murdered as part of a conspiracy to discredit the eponymous technology and the subculture that has fully adopted it. Nobody, not even the private investigator she hires to take the case, actually believes that Sharpe's mother was murdered. As it turns out, [[spoiler: a reactionary conspiracy ''did'' kill her to turn the public against TAP, but the methods used were different from how Helen initially suspected]].
* TheGreatPoliticsMessUp: "Yeyuka" was written in 1997, and as a result has the Democratic Republic of the Congo still called Zaire by characters who live in the 2020s.
* VillainProtagonist: "The Moral Virologist" has one. The first few paragraphs lead the readers to think that Shawcross is [[SignatureStyle your typical]] ScienceHero; however, he is [[TheFundamentalist anything]] [[MadScientist but]].
* WorthyOpponent: Despite their previous history, Stoney actually considers Hamilton this in "The Oracle" after their televised debate, as Hamilton is actually able to make a cogent argument, relatively free of LogicalFallacies, (instead of the typical creationist fare) which references actual mathematicians and scientists, rather than the medieval philosophers that Stoney was expecting.
* {{Zeerust}}: Though still hard science fiction, some of the stories Egan wrote in TheNineties, such as "TAP", haven't aged well because of VirtualReality being an important plot point. ([[TechnologyMarchesOn Though given recent advances]], [[SubvertedTrope this may swing back to respectability in a few years]].)
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