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Quarantine

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It causes riots and religions. It has people dancing in the streets and leaping off skyscrapers. And it's all because of the impenetrable gray shield that slid into place around the solar system on the night of November 15, 2034.

Some see the bubble as the revenge of an insane God. Some see it as justice. Some even see it as protection. But one thing is for certain -- now there is the universe, and the earth. And never the twain shall meet.

Or so it seems. Until a bio-enhanced PI named Nick Stavrianos takes on a job for an anonymous client: find a girl named Laura who disappeared from a mental institution by the most direct possible method -- walking through the walls.

280 pages, Paperback

First published January 1, 1992

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About the author

Greg Egan

99 books2,717 followers
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.

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Displaying 1 - 30 of 449 reviews
Profile Image for Manny.
Author 45 books16k followers
March 6, 2021
- This court is now in session. Would the defendant please rise. Greg Egan, how do you plead?

- Not guilty, your honour.

- Mr Egan, what is your profession?

- I am a science-fiction writer, your honour.

- What kind of science-fiction writer?

- An Australian science-fiction writer, your honour.

- Your country of origin is immaterial, Mr Egan. We wish to ascertain what sort of science-fiction you claim to produce.

- Some people quite like it, your honour.

- Mr Egan, I see I shall have to phrase my questions more precisely. Are you what is generally known as a "hard" science-fiction writer?

- I have been called that, your honour.

- Do you accept this description? Is it one you consciously attempt to live up to?

- It's hard to say what's conscious and what's unconscious, your honour. I'm just trying to tell a story.

- Mr Egan, please restrain your feeble attempts at humour. You generally manage to do that in your published works. Would you care to explain to the court, in your own words, what you consider differentiates "hard" science-fiction from other kinds of science-fiction?

- Well your honour, I would say that it involves making a serious attempt to get the science right.

- Thank you, Mr Egan. Now, you have been referred to at various times as "the king of hard science-fiction". You are presumably aware of that?

- I have seen the expression, your honour.

- Have you seen it often, Mr Egan?

- Quite often, your honour.

- When did you see it last, Mr Egan? We are trying to establish what "quite often" means.

- Your honour, about a minute and a half ago I received a mail from someone called nrrrdgrrrls4eva who used that phrase.

- Since you appear to have this document to hand, Mr Egan, would you perhaps read it out to the court?

- Yes your honour. It starts like this. Greg, you are the king of hard science-fiction. I am now rereading Orthogonal again, I just wanted to you to know that every time I get to the bit about the quaternions and the spinors it makes me so wet that I--

- Thank you Mr Egan, that will be sufficient.

- Yes, your honour.

- Mr Egan, does quantum mechanics play an important part in your novel Quarantine?

- It does, your honour.

- In what way would you say that you treated the subject of quantum mechanics in that work?

- In a non-standard way, your honour.

- Mr Egan, do you know anything about quantum mechanics?

- I like to think I do, your honour.

- In that case, can you tell us how you believe other experts on quantum mechanics would view its treatment in your book?

- It would depend on the person in question, your honour.

- Do you imagine that most of them would consider your treatment credible?

- Probably not, your honour.

- Would they, perhaps, consider it implausible in the extreme?

- They might, your honour.

- Would they go so far as to call it complete and utter nonsense?

- I can't rule that out, your honour.

- Yet you sell your books as "hard science fiction". Do you consider that you are treating your readers in a fair and ethical manner, Mr Egan?

- Your honour, I have very limited influence on my publisher's marketing department.

- Mr Egan, we want to know why you did this.

- With all respect, your honour, the notion of "motivation" is philosophically slippery. And when creating literary works, the reasons behind an author's artistic choices may be particularly hard to reconstruct. Plato, in The Republic--

- Mr Egan, I shall have to ask you to keep to the point. Plato is not on trial here. And he was not a science-fiction writer.

- Your honour, the late Mr Kingsley Amis argued, I think quite convincingly, that Plato's Critias is perhaps the first clear example of--

- Mr Egan, I find it tedious to repeat myself on such elementary matters, but Plato wrote philosophy, not science-fiction. I do not suppose that you consider your novel to be a piece of philosophy?

- As a matter of fact, your honour--

- Thank you. I am sure we would all enjoy continuing this discussion, but unfortunately we have a schedule to keep. Have the members of the jury reached a verdict?

- We have, your honour. We unanimously find the defendant guilty on all counts.

- Sentencing will be postponed until next week. I need to think of something sufficiently cruel and unusual.

- Yes, your honour.

- That brings this session of the Court of Public Opinion to a close. Thank you and good afternoon.

[I also have a serious review here]
Profile Image for BlackOxford.
1,095 reviews70k followers
June 13, 2020
Mods, Moods, and Modes

To measure something is to change it, to cause it to become fixed by eliminating its infinite possibilities. This is a well-established principle of quantum mechanics. If that is true, human beings have much more to answer for than we thought. As our techniques of measurement have become more refined and better able to reach further into the far reaches of the cosmos, we have left a path of destruction literally as far as the eye can see.

The really spectacular advances in artificial intelligence in Egan’s world of Quarantine are not the ‘mods’ (apps) of data manipulation, communication, and presentation. Rather they are those which can control our basic moods - alertness, rationality, even our loyalties. There are experimental mods which are so advanced that they can alter our very mode of being. This is the real import of AI - not how it mimics human consciousness but what it does to human consciousness

Philosophically speaking, human are the thinking creatures. Thinking is what makes us different, possibly unique, from other sentient beings. Thinking is our mode of being and the essential cause of our destructive rampage throughout the universe as we measure, analyze, and judge it. It is what we value above all else - the ability to value at all - and what we are ‘hard-wired’ to pursue. But by thinking we are reducing the complexity of everything we think about. Through the quantum effects of reflective thought the universe becomes a less diverse entity. We are literally dumbing it down as we learn about it.

But suppose there were a mod which could effectively re-wire our brains, by-passing the normal neural processes that involve quantum effects. Perhaps we could then avoid the adverse consequences of thought. We could stop being in a state of permanent warfare with the rest of physical creation. Would such a leap represent a scientific breakthrough or an apocalyptic spiritual, moral and physical disaster?

Eagan is a genius. It is very possible only he knows the answer.

Postscript on Corporate Sociology

Quarantine is densely packed with speculative technological ideas and their consequences. But it also contains an important thread about human organization which is highly insightful in its own right. This is the issue of corporate structure and is implications for human behaviour.

The protagonist Nick is forcibly recruited to an entity called The Ensemble. A mod is inserted in his brain which ensures that he will be totally loyal to the interests of The Ensemble. He is aware of this but he is also aware that he can do nothing about this enforced loyalty except to go mad. The interests of The Ensemble are essentially his own interests.

However during the course of his duties Nick discovers that there are factions within the group that runs The Ensemble. This group, called the Canon, is composed of people who have not been implanted with the loyalty mod; and they have different views about what their interests and those of The Ensemble are.

One of his similarly loyal colleagues makes the point to him that only those who have the loyalty mod are actually qualified to judge what the interest of The Ensemble really are. But even this presents a dilemma because even such loyal and altruistic corporate citizens have different views about what the interests of The Ensemble are.

The only method available to resolve this situation is conversation. In this conversation, the views of each loyal participant must be accepted in their entirety and without compromise. These views are then used as the way to find the wider purpose in which the diverse views fit as special cases. The loyalty mod does not relieve Nick of the obligation to make judgments of value; it insists upon these judgments.

This is a profound vision of corporate organization. What Egan has demonstrated is that loyalty to a corporate entity does not mean abandoning one’s individual values. Rather, the identification of the corporate interests, of joint purpose, depends crucially on the preservation and transformation of those individual values. The idea is remarkably close to that of ‘loyalty to loyalty’ by the American philosopher, Josiah Royce: https://www.goodreads.com/review/show.... This theme alone would make Quarantine a masterpiece of sociological thought.
Profile Image for Manny.
Author 45 books16k followers
March 6, 2021
This book is an interesting philosophical novel masquerading as a slapdash SF thriller, and at first I had trouble understanding what it was about. It's one of those deals where the world-building contains two elements which at first sight appear to have nothing to do with each other. On the one hand, computer-brain interfaces have improved to the point where virtually any new knowledge or behaviour can be inserted into your head as a "mod", a rapid rewiring of the neurons mediated by suitably constructed nanobots. On the other, the main plot is based on a highly implausible version of quantum mechanics:

[I also have a frivolous review here]
Profile Image for Bradley.
Author 9 books4,811 followers
June 21, 2018
I've had Greg Egan on my radar for a long time but aside from a lucky chance encounter with a novella, it still took me almost two decades to finally break down and read him! It wasn't his fault. That lies entirely with me. I'm absolutely ashamed.

Why? Because this hard-SF novelist is unashamedly tackling some of the hardest quantum physics interpretations, (smearing possibilities and collapsing the wave functions of reality) to very, very courageous levels.

The writer runs with a loaded gun with a safety off. It's pretty awesome. The risk he takes from turning a cyberpunk Private Investigator novel into a completely sidelined thought experiment including the mythical Observer and the death of all the wave functions to create a single reality, multiplying it by a few observers, and then eventually to the whole Earth, is not an end ANYONE ought to miss. I cheered. I gasped. I whooped.

Am I explaining this too esoterically? Possibly. Okay, let's back up. The Earth is suddenly quarantined in a quantum bubble to protect the rest of the universe from summarily changing realities willy-nilly because we THINK it into being. It starts out as quantum tunneling on the macro scale, cheating at cards, getting hugely improbable number sequences right, but then we go deeper and deeper down the rabbit hole where multiple worlds can be chosen from at will, thousands, hundreds of thousands, and each die as the "best" possible world becomes real. Now let's throw that into the stew and add more people. How about adding everyone to that powerful quantum schedule? What happens when we all get the ability to be gods?

Yeah, Egan attempts just this. :) Brilliant attempt, too!

So why didn't I give it 5 stars? Because great ideas don't always equate great fundamental stories with plot and characters. There's nothing wrong with this one, but most the plot and characters are puppets to the need to make clear what is going on, science-wise. I like good exposition when I need it to follow the intent of the author. In this case, it's absolutely necessary. And delightful. But it necessarily slows down the plot, too. Like, to a crawl.

Fortunately, it was never boring to me. Just uneven. No harm, no foul! And what we have here is a novel of quantum possibilities gone totally nuts. :) I LOVE THIS!
Profile Image for Glenn Russell.
1,491 reviews13.1k followers
Read
September 4, 2024


Quarantine - Greg Egan's imagination ablaze. There's so, so much going on in this hard SF novel. Below are seven hits of futuristic stuff contained in its pages. Incidentally, I was warned by Goodreads friend Manny Rayner that Greg has created a universe with a different quantum mechanics from our own, a universe where men and women can "control the collapse of the wavefunction and select which branch will be left." Anyway, here goes. I hope what I've noted will encourage readers, even liberal arts types like myself, to pick up a copy of Quarantine and blast off to the year 2067 with Greg Egan. What a fabulous adventure.

THE BUBBLE
On November 15, 2034, our solar system was enclosed by a perfect sphere. Along with every other sensible person on the planet, the tale's narrator, a private investigator named Nick Stavrianos, recognizes there is only one plausible explanation: vastly superior aliens constructed a colossal bubble to seal off our solar system from the rest of the universe, effectively putting us in quarantine. The looming question that has remained unanswered for more than three decades is: why?

APOCALYPSE SOON
Nick tells us there have been all sorts of conjectures and theories put forth. “A few intellectually rigorous killjoys argued that any explanation to which humans could relate was probably anthropomorphic nonsense, but nobody invited them onto talk shows.” As perhaps expected, fundamentalists cash in on one more sign portending the end of the world. However, the most extreme group, Children of the Abyss, formed by young men and women born after Nov 15, 2034 and proclaiming “this is the Age of Mayhem” pose the most serious problems. To date, by things like poisoning water supplies and blowing up buildings, they've killed nearly 100,000 people. And, gulp, these radicals are active in forty-seven counties.

LAURA
An anonymous client hires Nick to find Laura Andrews, age thirty-two, who has suffered brain damage since birth. Although Laura can walk clumsily, her ability to understand the world and communicate has always been on the level of a six-month-old baby. Therefore, doctors, staff, security at the Hilgemann Institute, the police, and everyone else are baffled as to how Laura could have disappeared from the institute, where she has been an inpatient since the age of five. She surely couldn't have escaped by herself – Laura could barely turn a doorknob to open a door. Was Laura possibly kidnapped? Nick utilizes sophisticated technology to explore all the possibilities without much success. But when Nick connects the fact that Laura Andrews was conceived on or close to November 15, 2034, the infamous Bubble Day, this astonishing futuristic SF plot torques, twirls, and thickens.

PROGRAMMING MODS
Men and women can purchase various neural modifications (mods) that interact with their thoughts. For example, Nick has a mod that functions as a kind of internal smartphone and another mod that generates a hallucination of his dead wife, Karen, allowing Nick to carry on a conversation and receive advice from her. The mods are tiny; some mods are microscopic. All mods can easily be placed on the side of the head.

PERSONALITY MODS
A darker aspect of neural modification can be seen in those that alter behavior and identity. During his time on the police force, Nick used six standard "Priming mods," which he admits made him less human but a more effective officer. One mod even numbs his grief over his wife's death, reflecting his struggle with genuine human emotions. In another scene, Nick fumes, "Why put up with four more hours of boredom and anxiety? For the masochistic thrill of enduring real human emotions? Fuck that; I had my dose of that this morning, and nearly walked away from the case." These instances raise important questions about humanity and technology.

Then there are mods that are forced on individuals, like the Puppet mod, which makes a person simply repeat what an organization or group wants them to say. Or the Loyalty mod, whereby a person offers unflinching allegiance to whatever the group desires. Now, does all this neural modification sound a tad sinister? You bet it does. In this way, Greg Egan has given us a cautionary tale prompting serious philosophic reflection.

A DETECTIVE'S HELPERS
Prior to entering a top-secret building at night, Nick sends out a computerized scanning system in the form of a mosquito that, in turn, is equipped with a dozen minuscule chameleons. Nick receives the information he needs. “Finally, it checked back with the chameleons, who'd cracked the security system's signal validation protocol, and reported that, after sampling all thirty-five cables, they'd identified twelve by means of which a useful set of contiguous blind spots could be created.” If such surveillance can be conducted on a top-secret facility, just think of the average person's right to privacy. Obliterated!

MIGHTY MULTIVERSE
All of the above is from the first half of the novel and sets the framework for Greg Egan's version of a mind-boggling expansion of quantum mechanics and the eigenstate (please see Comment #1 below). And, yes, at the end, Greg ties all the physics fireworks in with Laura, The Children of the Abyss, and The Bubble. Phenomenal accomplishment. I encourage all readers to accept the challenge and tackle Quarantine.


Australian author Greg Egan, born 1961 - Greg takes pride in not having any photos of himself available on the web. This photo is the way I picture the outstanding SF novelist writing at his computer.
Profile Image for Claudia.
1,010 reviews755 followers
July 17, 2020
I was twelve, […] the night the stars disappeared from the sky. (Spin)

versus

I was eight years old when the stars went out. (Quarantine)

Had Robert Charles Wilson read this prior writing Spin or is just that great minds think alike? Anyway, despite the initial surprise at this similarity, the resemblance between the two works stops here.

Quarantine starts out as a detective story: our main character, Nick, a private investigator, is hired to find Laura Andrews, a thirty-two years old woman who escaped the mental facility whose resident she was, being in a complete vegetative state.

But, with each page, the complexity of the story grows exponentially. If you’re familiar with Egan, you know that plot and characters are just side-lines. The central part of his books is expanding on mathematical & physics concepts; all others are just part of the structure. Here the focus is on the wave function collapse.*

What he does in this story not only entangles your neurons in the complexity of quantum mechanics applied to a macro scale, but also touches more sensitive topics such as free will, consciousness and dealing with emotions.

I decide to take the stairs? Maybe I have no choice in the matter; maybe every last detail of my thoughts and actions has been, or will be, selected by my smeared self. But the illusion of free will remains as compelling as ever, and I can’t (literally can’t?) help thinking that the choice was mine.

‘So what? Everyone’s in an artificial state. Everyone’s brain is self-modified. Everyone tries to shape who they are. Are neural mods so terrible, simply because they do it so well – because they actually let people get what they want? Do you honestly think that the brain-wiring that comes from natural selection, and an accidental life, and people’s own – largely ineffectual – striving to change themselves ‘‘naturally’’, is some kind of touchstone of perfection? Okay: we spent thousands of years inventing ludicrous religious and pseudo-scientific reasons as to why all the things we couldn’t control just happened to be the best of all possible alternatives. God must have done a perfect job – and if not God, then evolution; either way, tampering would be sacrilege. And it’s going to take a long time for the whole culture to grow out of that bullshit. But face the truth: it’s a heap of outdated excuses for not wanting the things we couldn’t have.

And that’s why I read Egan: because his imagination in extrapolating on mathematical/physics notions is astounding; no other does it better than him when it comes to hard SF.

* For those of you who want more details about it, here is an essay in which the author explains why he chose this concept for his book, where the science end and where the science-fiction begins: https://www.gregegan.net/QUARANTINE/Q...

Furthermore, for math afficionados, here are some more details on the probabilistic events in the book: https://www.gregegan.net/QUARANTINE/R...
Profile Image for David Katzman.
Author 3 books533 followers
June 12, 2019
What improbable collapse of quantum potential states has resulted in the fact that immediately after reading a science book about confronting the measurement problem in quantum physics that I should read a science fiction book that is centrally about the measurement problem in quantum physics???

Quarantine is an extremely odd book. It’s a book of ideas. It’s bizarre, surreal and mind-bending and also grounded in quantum physics. As I discuss in my review of What is Real?: The Unfinished Quest for the Meaning of Quantum Physics by Adam Becker, there are several primary theories (with multiple variations) that purport to solve the measurement problem of the Schrodinger Equation and explain what that equation says about reality. Becker sees the traditional Copenhagen Interpretation—despite being relatively the most popular theory among physicists—as the weakest solution and one that instead of actually confronting the measurement problem, looks the other way and says that there is no measurement problem. (See my review for more for more on this topic.)

Egan world-builds the premise of his novel by assuming the literal truth of one of the currently less-favored solutions to the measurement problem, one that Einstein himself considered illogical and absurd. That said, it makes for an interesting premise to project out a story. Egan begins with the theory that part of the human brain (some theorists have even described it as “consciousness,”*) is responsible for collapsing the wave function. He then lays on top of this premise, the fantastical idea that

With that as the basis, the storyline itself is a science fiction noir espionage/thriller involving evil corporations, cults and technology-based body modifications. It’s a fascinating story that is occasionally dragged down by extended scientific lectures and debates. I couldn’t quite tell if he was intentionally diverting the story into these “talking head” types of scenes as an almost absurdist distraction, or if that’s just how he wrote it, unironically. Sometimes I found the talking-head scenes amusing while other times I wanted him to just move on. Yes, Quarantine is driven by some rather absurd extensions of the Copenhagen Interpretation, but even so…they aren’t any more insane than quantum physics itself is. I think Egan did a pretty remarkable and highly inventive job applying cutting edge quantum theory to a wild ride of a story that I found hard to put down. If you enjoy science fiction, particularly of the cyberpunk variety, then this book is highly recommended.

*Since consciousness is an abstraction, or as philosophers would label it, qualia...an inner representation of neurological functions...how could qualia affect matter directly? That is, how could something immaterial affect a particle that is merely "observed?" It's far from clear that this is possible or even what observation exactly is.
21 reviews6 followers
February 28, 2022
I'm not a huge Greg Egan fan. But that may well be because he outgrew me, and I stopped keeping up with the right varieties of science to really appreciate his work. However, Quarantine, one of his first novels, is one of my favorites. I reread it over the past few days, but I first read it when it came out. We older SF fans talk a lot about the sense of wonder (aka sensawonda). But over the years, I got less and less of that sense from the physics/chemistry parts of SF and more from things like alien cultures (often thinly disguised human cultures, which I then went and read about.)

But Quarantine fully awoke that feeling, and did it with Quantum mechanics and (QM nearly inevitable fictional co-star) philosophy. Given Quarantine is a QM book, it is delightful that observation by the reader plays a major role in determining what kind of book it is. Depending on how the wave function collapses Quarantine may be a first rate horror novel/psychological thriller, a detective story that is the product of a marriage between cyberpunk and noir, an understated tale of tragic love, a first contact story, or a delightful exploration of some wild implications of QM. Of course, the book is all of these at once until the reader decides which it is.

I'd recommend this book to people who like the their SF to have the science up front and center (not technobabble, but science), to people who liked cyberpunk but want something somewhat different, and to people who want weird worlds conveyed without weird literary techniques.
Profile Image for Stuart.
722 reviews330 followers
May 11, 2016
Quarantine: Cool quantum mechanics, pedestrian plot
Originally posted at Fantasy Literature
Greg Egan is an Australian writer of hard science fiction who specializes in mathematics, epistemology, quantum theory, posthumanism, artificial intelligence, virtual reality, etc. When you pick up one of his books, you know you will be getting a fairly dense crash course in some pretty outlandish scientific and mathematical ideas, with the plot and characters coming second.

The cover blurb advertises Quarantine as “A Novel of Quantum Catastrophe,” and the back describes “an impenetrable gray shield that slid into place around the solar system on the night of November 15, 2034” causing riots and chaos. However, the book mainly takes place in Perth and New Hong Kong, which was relocated to Australia after the Chinese took over. So don’t expect too much galaxy-spanning space travel or conventional aliens. This book is about quantum physics, simultaneous ‘eigenstates’ when humans use neural ‘mods’ to ‘smear’ themselves before collapsing back into a single state of existence, erasing those infinite possibilities.

The story centers on private investigator Nick Stavrianos, who is asked by an anonymous client to investigate the disappearance of Linda Andrews, a brain damaged patient at the Hilgemann Institute who, one day, disappeared from her room without a trace. It’s a fairly typical scenario, designed to reveal elements of the plot as his investigation progresses. Surprise, surprise, this is not just a random disappearance, but the tip of a much more elaborate conspiracy by shadowy organizations to exploit the neural ‘mods’ that could blow the lid off our conventional reality quicker than you can say ‘cookie-cutter private-eye story about collapsing wave functions and reality-altering nanotech mods.’

The early part of Quarantine establishes the nanotech-filled world of the 21st century, brimming with technological wonders but also with religious mania and terrorism inspired by the Bubble that surrounds the solar system. It’s not a pleasant world, and technological espionage is commonplace. Once Nick and Linda’s backstories are established, the book delves into its main subject matter, a revolutionary new mod that could allow the user (the ‘observer’ in the Schrodinger’s Cat experiment) to choose from an infinite number of quantum probabilities while ‘smeared’ when the wave function collapses back into a single reality. If this can be controlled, the possibilities are unlimited — pursuing personal profit, improving the lot of society, or perhaps something much more radical.

Nick gets deeply embroiled in the conflicting factions seeking to control this mod, and the mechanism by which his loyalties are controlled is quite fascinating — one of the better ideas in the story. It’s not until things get extremely technical and complicated that we discover the connection between this reality-bending mod and the Bubble that mysteriously appeared at the beginning of the book.

I’ve always been interested in quantum mechanics, Multiple Worlds Theory, nanotech, etc., and all the mind-bending possibilities that these ideas entail. Egan spends enough pages explaining quantum ‘smearing’ and ‘collapsing’ that even a complete layman like myself, who loves hard science fiction ideas but hates differential equations and complex calculations, to understand the basics. As Egan explains in a very illustrative article on his blog (Quantum Mechanics and Quarantine), he chose a very unlikely interpretation of quantum mechanics and wave function collapse in order to make an exciting and imaginative science fiction novel. In general, I think he succeeds at this, though at the expense of in-depth characterization. If that appeals to you, by all means give Quarantine a try. Out of all the possible quantum probabilities, this is probably one of the better iterations.

Notes on the Audible Studios version:

When I discovered that you can get many of Egan’s books in Kindle and Audible versions for the COMBINED price of $4.98, I figured that was just too good to pass up. In particular I snapped up Quarantine, Permutation City, and Diaspora as promising titles. Then I noticed the ratings on Audible were surprisingly low (the low 3s), and discovered that most of the audiobook readers liked the books but pilloried the narrator Adam Epstein for being completely inept — boring, bad accents, painfully slow, mispronouncing words. No wonder its so cheap, I thought. Maybe this was a mistake. But I knew I could at least fix one thing, the overly-slow narration speed, by simply selecting 1.5x speed, my normal pace. Perhaps some listeners aren’t aware of that option.

Long story short, they were right that Adam Epstein is NOT a particularly good narrator, especially his atrocious Australian and Chinese accents and mispronouncing of words like Taoist (he read it as “T” rather than “D”) or ASEAN (he read it as “A-Shawn” instead of “As-ee-an”), which suggests he doesn’t listen to financial news at all. Surprisingly, I thought he soldiered through the technical parts fairly well, though they inevitably sounded like a textbook at times. However, I decided to forgive this since I am getting Greg Egan’s audiobooks for just $1.99 each.
Profile Image for Chris Berko.
484 reviews136 followers
February 18, 2022
Mind-numbing, -blowing, -expanding novel. Fun beyond measure, I can’t get enough Egan right now.
Profile Image for Hank.
1,009 reviews108 followers
September 5, 2019
My head still hurts from reading this one, is it my head or one of my eigenstates' head?
A book that takes the idea of each individual choice creating a separate path or separate you to an extreme AND tries to define it mathematically.

Egan is sort of like PKD with a Physics degree, there is an incredible amount of interesting commentary packed into this, less than 300 page, book from bio mods changing who you are, but who cares because it is the same as drinking a cup of coffee, to this whole changing the universe idea just because you think it. I almost started over right when I finished just to see what I could get out of it the second time.

My 2 quantum physics classes in college just barely prepared me, for sort of understanding where Egan got his math and because of that I can't really recommend this to anyone other than hard sci-fi fans or someone who is searching desperately for a PKD substitute.

3.5 stars rounded up because this IS my cup of tea, demerits for the too long eigenstate discussion which made part of the book a slog. I am definitely going to read another Egan book.
Profile Image for Bart.
441 reviews115 followers
November 9, 2020
What starts as a detective set in 2067 quickly turns into a head spinning novel about the possible existential effects of the Copenhagen interpretation of quantum mechanics – more specifically the consciousness causes collapse variant. In short: humans observing stuff limits the number of possible worlds.

If you thought the popcorn sci-fi of Dark Matter was hard, well, this is the real deal. On the other hand, compared to the only other Egan I’ve read so far – the brilliant Schild’s Ladder – this is an easier, more accessible book.

The first half is smooth reading: Nick Stavrianos, a hardboiled PI, investigates a kidnapping/closed room mystery. The specifics of the setting – Earth quarantined by “an impenetrable gray shield that slid into place around the solar system” in 2034 – seem a cool yet inconsequential backdrop at first. It’s brilliant how Egan manages to weld the two mysteries together.

The same goes for the other science fictional thing Quarantine features: mental modifications people install in their brains via nanobots. Again seemingly gimmicky in the first half of the book, it nonetheless gives the detective story a futuristic, exciting edge that would not be out of place in a Hollywood action flick.

But as the story progresses (...)

Full review on Weighing A Pig Doesn't Fatten It
Profile Image for Erik.
343 reviews322 followers
July 20, 2020
An Egan novel, I’ve learned, follows a particular structure. It begins, like every other novel, by establishing the setting and characters and their aspiration & motivations. Usual stuff. Nothing crazy. Just ease the reader in, a normal sci-fi novel, nothing to worry-

SUPER. EGAN. MODE.

Animated gif of Goku powering up

-and then it unleashes the math and science THUNDERSTEM! Egan lets loose with the true sci-fi aspect, building a wild ride out of an imaginative extrapolation of some major science idea.

Same story with Quarantine, technically Egan’s second published novel, but typically considered his actual debut.

The novel starts out as a detective / mystery novel, in which the main character - an ex-cop turned private investigator - is hired to find the whereabouts of a mentally retarded adult woman who somehow managed to escape her caretaking facility. Which occurs roughly 30 years after a giant black hole-esque “bubble” surrounded the solar system, cutting us off from the rest of the universe. That is, the titular quarantine.

While lacking the stylistic flair of a Hammett or Chandler, all the trappings are there. A brave, if stoic, protagonist. A seemingly simple case that turns out to be not so simple at all. A mysterious and/or uncooperative client. Etc, etc. As someone who loves noir detective (and indeed wrote a novel in that style), I found this part to be satisfactory. But I wouldn’t call it great.

But then the joy of an Egan novel isn’t its first half. It’s the second half’s Super Egan Mode, where his imagination truly shines. Which I’m now going to talk about, so…


***SPOILER WARNING***


The sci-fi premise of Quarantine relates to the observation problem of quantum mechanics. In QM, quantum particles are treated as probability waves that only “collapse” to a particular real state when observed.

Which is a problem because we have no idea about the actual physical mechanism of collapse or observation. Assuming that collapse even occurs and isn’t merely some sort of mathematical artifact. And what counts as an observation anyway? As John Bell quipped, “Was the wave function waiting to jump for thousands of million years until a single-celled living creature appeared? Or did it have to wait a little longer for some high qualified measurer - with a PhD?”

Quarantine posits that the universe actually began in a perpetually uncollapsed state and that uncollapsed intelligent beings evolved within this universe. Which… well, I’d never considered that and it’s difficult to imagine, but doesn’t seem impossible? If the quantum world can exist in a largely uncollapsed state, why couldn’t our macro world? I mean, “micro” and “macro” are arbitrary, human-centric distinctions - who’s to say that our “micro” world isn’t some other species’ “macro” world, and vice versa?

Well, regardless, mammals on Earth evolved neural structures capable of initiating a collapse.

Which is problematic for the rest of the universe and those “uncollapsed” intelligent beings & civilizations. When we look to the stars, we collapse them into only those configurations which would cause us to see what we see. Which isn’t terrible - that leaves a lot of leeway, especially when you consider we’ve yet to directly observe dark matter or dark energy - over 95% of the universe. But as our instruments advance, we increase both the depth and breadth of our observations and destroy yet more possibilities. Hence… the Quarantine imposed on us.

The main character actually gains the ability to turn off the collapse-inducing part of his brain and (crucially) the ability to change the probabilities/weight of the various possibilities. Thus he can choose WHICH potential state ends up being the real “collapsed” one. But even then it’s not really “he” doing the choosing but this sort of meta uncollapsed congolomeration of infinite versions of himself, a point of view that we never get to see first-hand.

To actually write such a perspective requires a bit of narrative flubbing - you get this conceit where what we, the reader, are reading represents only a sort of retroactive memory of the actual chosen “collapsed” state. But we also go down a lot of dead ends, in the sense that we end up reading the perspective of one version of the protagonist who actually ends up not being the “real” one.

It’s a clever bit of dramatic irony. Reminded me of The Demolished Man, which involves the main character misreading a secret code that the reader is perfectly capable of noticing. And much of the protagonist’s angst over whether he would turn out to be the “real” one reminded me of the character Angier in the film The Prestige, when he said: “It took courage... it took courage to climb into that machine every night... not knowing... if I'd be the man in the box... or the prestige.”

Now, all throughout this second half, I had this strong sense that it didn’t quite all add up, but I was never able to consciously articulate what it was. It seems ludicrous that our world could be stable - that, for example, this book review would somehow collapse to the exact same words for every single reader at every single time - if it were constantly fluctuating between collapsed and uncollapsed states.

And yet, in a sense, that’s how our world already is. We may look at a lawn-mower, for example, and it will appear completely solid and unchanging. But that isn’t the case. It’s just, from our macro perspective, we don’t really care about individual quantum particles. It doesn’t matter if every second a billion electrons tunnel out of their voltage wells to escape their atomic prisons because there’s a trillion trillion that don’t, enough to maintain the illusion.

But there’s a difference between that and an entire macro object - a whole person - collapsing into extremely unlikely configurations. As Egan wrote in his essay on the matter, decoherence (essentially, external elements interfering with an “isolated” quantum system) would ruin the whole thing.

Well, however the chips of reality may fall, it’s a fascinating thought-provoking read. But be warned: it is incredibly, though subtly, bleak.

In contrast to my experience with other Egan novels, spending the time to ponder Quarantine left me feeling depressed. Because, despite all the ludicrous, wild events of the novel, the final line is: “It all adds up to normalcy.” And he’s exactly right. Wonder and magic can feel as powerful and fiery as blazing stars, but in the grand scheme of life, they’re ultimately only microscopic pinpricks of light in a vast and overwhelming void of normalcy.
Profile Image for Whitney (SecretSauceofStorycraft).
680 reviews95 followers
March 10, 2025
3.5!!! This book started poorly- but then I had the Aha! Moment in ch 8. I realized this book explores 1 particular physics concept x1000 and is essentially a nerd using nerd physics to create plausible super powers…..once I got there I really relaxed into the story and had a fun time.

One day the stars disappear and it appears that Earth has been surrounded by an opaque bubble 🫧 like substance that doesnt not let anyone in or out. Our main character gets a loyalty module placed inside his brain by the company so he is happy to do nothing but his job, until someone reveals a secret workaround….

Dont mistake this book for a light read. The themes here went far beyond physics and also included mental health, some dystopian corporatations ruling employees thoughts and themes I cant reveal without spoilers…

The prose and the concepts are tarry and thick. I almost dnf’d, However, it was possible to understand after you wade thru that beginning section.
Profile Image for Sarah B.
1,270 reviews23 followers
December 15, 2019
I started reading this book to complete my ABC challenge, as the only letter I needed was a "Q"...but to my surprise I liked the book a lot more than I had ever expected. Also I had no idea what it was about; only that it was science fiction..so I was surprised to find out the main character was an ex-cop who was now doing detective work.

This story takes place in the future where advance tech is common. One type of this tech that is central to the story is mods that are downloaded into your brain and they run programs. The detective has one that can keep him calm by shutting down his emotions as it's important for police work. But mods can do all sorts of stuff and some might be illegal. And he has lots of mods.

Thirty-some years ago something bizarre had happened: the stars had vanished! This event is part of the story. The science is very big in this book, especially quantum mechanics. Now I never dreamed I'd enjoy a book so much about quantum mechanics but to my utterly surprise I did. And before I started reading this I truly didn't know anything about it but I watched a few simple videos on YouTube and they gave me a general background on the subject. And I suppose it helped but the novel does explain it but I am glad I watched the videos. I just found this book far more interesting than the very famous book I read before this one (Night Circus) - I guess the unusual plot and the science just engaged my mind.

In the story the detective sets out to find a missing woman and he ends up in New Hong Kong. But while there he ends up trying to save the world. As noted above, this story is very science heavy and it may not be for everyone. The plot deals with alternate realities, chance and of course why the stars vanished.

It's not an action story. It's more about unraveling a mystery so the detective can find out what's really going on. And the plot does have several twists. He thinks he has it figured out but then it changes.

This is the first book in a trilogy. I enjoyed this one enough that I'd like to read the others. I think it does a good job of explaining very complicated science in a way that most people can understand and what better way to do that than in a story?
Profile Image for Roddy Williams.
862 reviews39 followers
October 26, 2014
At the very hard edge of hard sf's furthest boundary is Greg Egan. One could describe Egan as one who writes fiction for scientists to read. This should not deter anyone else from reading his work though.
The premise here is that (as in Robert Charles Wilson's 'Spin') an impenetrable barrier has been thrown around the Solar System, blotting out the stars.
Nik Stavrianos is an ex-cop private detective in a near future Australia where many residents have been gene-sequenced to produce melanonin and are therefore now black. he left the service when an apocalypse cult (The Children of The Abyss) killed his wife but he keeps her within his consciousness as a virtual recording to occasionally spend time with him.
Nik's latest case is to find a catatonic woman who somehow escaped three times from a high-security nursing home. The third time, so Nik discovers, she was kidnapped and taken to New Hong Kong. Nik's investigations lead him further than he would have imagined, into a company where the quantum nature of reality is being discovered and explored.
The lead character's profession and backstory immediately give the novel a noir feel. It's a subtle touch.
Undeniably the science seems faultless if at times a little impenetrable, but having said that, fascinating. Heisenberg, Schrodinger's Cat and the infinite multi-parallel universe come together to connect the woman's disappearance with the mysterious barrier surrounding the solar system. Amazing brain-workout stuff.
Profile Image for David.
568 reviews8 followers
June 1, 2015
The story revolves around the concept of the "observer effect" in quantum physics (the idea that what occurs in the world is based on multiple possible variants each of which exists simultaneously until some sort of "observation" causes a single version to become the only reality).

Readers who can experience the bizarre consequences of Egan's interpretation of quantum physics as magic - and can flow with the magic making its rules as it goes along - will find a unique and incredible landscape.

I've struggled with the unsatisfying oddities of the observer effect, wave-particle duality and such in the past. The thing is, (for me) experimental results don't seem to give a coherent picture, as I tried to express a few years ago in this short article: http://hardsf.org/Ques2Slt.htm

As a result, the book brought up my problems with "quantum philosophy". I doubt this will impact many readers as it affected me. So, my rating of the book probably has less to do with the literary or speculative quality of the book than it reflects how the above issues complicated my reading of it.

The book begins as an SF detective mystery, but transitions to a story about trying to understand possible ramifications of the observer effect (and controlling it). The book also envisions using nanotech to "rewire" areas in a person's brain in order to perform functions other books describe as being done by "neural implants".
Profile Image for RG.
3,087 reviews
February 18, 2018
I remember reading this while I was in high school and it blowing my mind. I didnt understand some of it. Might be inetersting to re read to see what my older self thinks.
Profile Image for Jason.
1,179 reviews282 followers
September 21, 2011
4 Stars

I am giving the overall of this book 4 stars only because Egan is not afraid to write hard science fiction. This is my second Egan novel that I have read, Clockwork Rocket (a book that I loved) being the first. Greg Egan is not afraid to use fiction to explore real science, physics, quantum mechanics, and deep philosophy.

This book Quarantine, a first in a trilogy is focused around quantum mechanics, specifically around a measurement known as Schroedinger’s Cat. “Quantum mechanics describes microscopic systems—subatomic particles, atoms, molecules—with a mathematical formalism called wave function. From the wave function, you can predict the probabilities of getting various results when you make measurements on the system.” The multiverse theory has a strong basis around this, around the fact that for every observation made by man, a new universe is created. All outcomes are realized. This is fascinating stuff that is right up my alley.

This book centers on our protagonist Nick Stavrianos, a private eye that is hired to find a girl that has gone missing from a high security hospital facility. The catch is, the girl Laura is a vegetable, non-responsive, and immobile. Did she get kidnapped? Did she somehow escape? Is there wrong doing? This mystery is the plot that is used to explore eigenstates, smearing, collapsing, observations, and finally genocide. Much of this book is philosophical as well as scientific as Nick comes to understand his role in the universe, the power of which he himself as an observer wields, and ultimately the perpetrator of cosmological scaled genocide.

I ate up the philosophy, gave myself mass headaches as I tried to wrap my beliefs around this freaking cool concept, and eagerly read on to find out more that will mess with my head. Egan does not hold back, nor does he dumb down any of his concepts to make them more accessible…Bravo! Even if you do not buy into these theories, this science, or their morale’s, you cannot help being totally impressed by the implications that Egan pens in this book.
The weakness of this book is the story as a whole. Although the plot works as a private eye type science fiction novel, and Nick is a decent protagonist, this book ends up being incomplete. It ends when the main threads are just being brought to a head. Questions are not answered. Plot lines are not completed, and we are left feeling like we were cheated. Move on to book two or get no satisfaction out of this one. In today’s market where everyone writes trilogies, this really makes me mad.

I am a huge fan of Greg Egan now, and totally recommend him to all that love really hard science fiction novels. Be prepared, much of his writing may leave you needing to get a pen and paper out to try and follow his writing just like you did back in physics class. Physics, Mathematics, and life’s big philosophical questions are all explored here. I loved the science, I liked the detective mystery, but I hated the way it ended.

Profile Image for zerogravitas .
202 reviews56 followers
May 17, 2019
This is exactly what you expect a book written by a mathematician to be. A living stereotype of Wigner's friend quantum mechanics explained to death.

The good side: the hard sci-fi concepts are really cool and interesting and the world building is awesome.

The bad side: sadly, the writer isn't experienced as a writer but he's using his books as a method to push his high flying concepts to people. The characters fall flat and I couldn't care much about the MC even though the book is written in first person and first person is supposed to make you root even for an unsympathetic character. Our MC feels a lot like a robot and honestly if they killed him and stuffed his brain in a jar I wouldn't have been bothered even a little.

Then another problem is that after he introduces his setting, the author goes skimming even more on character development by introducing new characters who read like one big single secondary guy/girl.

But the worst thing is that at some point the book derails completely into a mental experiment in quantum mechanics. You get this huge portion of the book where you just read pages and pages of logical derivations of the consequences of the quantum mechanical rules that were just introduced. Absolutely, this exercise is essential so that readers can follow how the setting rules will enforce what happens in act 3 of the book but the whole thing is so alienating and frankly tedious that I've read textbooks that are more exciting. At least textbooks have this habit leaving the exercise to the reader, habit which is sadly absent in this book.
Profile Image for Thom.
1,790 reviews69 followers
February 7, 2021
Starts off as a detective novel, then expands into a larger world of nanotech, alien contact and world manipulation through quantum mechanics. Comparable to The Lathe of Heaven, with more specifics given on the engines behind manipulation. Le Guin's book has the better story, though.

This book has a lot going on in a short count of pages. Some force that has put out solar system into a kind of "bubble", a doomsday cult reacting to that event, nanotech and brain modifications similar to smartphone "apps", potential alien contact and the aforementioned quantum mechanical manipulations. I can see how tags like "cyberpunk" landed on it, but this really is more of a "what if" story focused on quantum states.

I can't say much about the ending without spoiling the story. The author freely admits one of his interpretations is wrong, discussing it in a spoiler-filled essay on his website. Like most good science fiction, though, the exact method isn't the important factor in the examination. Discussions of the right to manipulate and which evils to choose are held between characters, with a lot of science in the mix, which could turn away more casual readers.

Quibbles aside, I liked it - a solid 3½ stars. While listed as part of a "series", the author has clearly stated they are not connected at all; this book stands alone. I plan to read other stories from Egan in the near future.
86 reviews
September 11, 2011
If you really like quantum mechanics and philosophizing on all of the strange reality that it entails, then you'll love this book. Otherwise, it's basically a mind f---. The ideas explored here aren't novel, but they are taken to such an extreme that it's hard to enjoy the book as a story instead of a thought experiment. And a challenging one at that - even with quite a bit of qm theory under my belt, I still ended up re-reading pages to make sure I kept everything straight. As a result, I only give Quarantine three stars - the first half is vibrant and enticing, but once the "real" thread of the story starts unraveling, you won't be doing much beyond trying to stay afloat.
Profile Image for ExtraGravy.
460 reviews29 followers
May 23, 2022
I enjoy how Egan plays with identity and technological modification, some of his novels are extreme in modification and some are less so, for Egan this was a "less so" and felt similar to a PKD novel - in the best possible way. There is a lot of overlap between how he deals with quantum woo and multiverse and how Neal Stephenson handles it in his great novel, Anathem. NS published Anathem 16yrs after Egan published Quarantine and I wonder if he was influenced by it.

Anyway, its a fun sci-fi novel, especially for fans of Greg Egan.
Profile Image for Susanna Neri.
607 reviews21 followers
October 7, 2020
3.5 questo libro mi ha lasciato sentimenti contrastanti, d una parte grande ammirazione per l'autore che ha costruito l'intero romanzo su una sola ipotesi, speculando su questa per tutta la storia, dall'altro ho avuto momenti di difficoltà nel seguire alcuni "spiegoni", del resto non si potevano evitare perchè sono i pilastri su cui si legge il libro. Forse da rileggere tra qualche anno
Profile Image for Soo.
2,928 reviews342 followers
February 6, 2021
Notes:

Thought provoking but failed to hold up within the story confines.
Profile Image for Jennifer.
3,070 reviews64 followers
February 15, 2017
I picked this up because I was drawn in by the private investigator/missing persons description, which the book definitely started with. Ironically, I had trouble concentrating on this book until it ended up taking a screeching turn away from a PI storyline and turned into a mindf*ck of a speculative science fiction novel; then, I was intrigued and reeled in until the end of this short "big idea" book.

It's incredibly difficult to describe what this books is about, but contrary to my experience with other "hard" speculative science fiction novels that establish a modified framework for the story's reality based on the author's mathematics or physics knowledge, Quarantine didn't make me feel like Greg Egan is a pompous ass or that he was condescending to the reader. This could be because the tone of his writing is matter-of-fact, which others might find dry, but which helped me go along with Egan's thought experiment, pun intended.

By using the many-worlds interpretation of quantum mechanics, Greg Egan explores the "big" questions about the nature of reality and the multitude of possibilities for the individual, society, and humanity. I think that knowing that this book was published in 1992 increased my intrigue, because it was prior to other novels that I've read that explore the idea of posthumanism, and its writing predates the widespread use of smart technology and apps, which are actually primitive versions of the brain "mods" in Quarantine.

This book definitely isn't for everyone, but I enjoyed it, since I'm the type of person who enjoys imagining systems that are technically not "real," that have user-specified parameters, and thinking, "Hmm, what would happen if we poked the system?"
Profile Image for neko cam.
181 reviews2 followers
February 1, 2015
As good sci-fi should, 'Quarantine' takes an existing area of scientific study, asks the reader to accept a key concession, and turns the dial up to 11. In this instance, the area of study is the observer effect in quantum physics and the concession is that the collapsing of a quantum wave function is a process that is triggered specifically in the brain of the observer. From there it explores all kinds of nuanced philosophical implications, which I won't detail for fear of spoiling the fun.

All this takes place within the framing device of a tech-noir detective story and an exciting adventure narrative. The characters are quite multifaceted and interesting - they're no mere conduits for the exploration of a hypothesis, but key players in an engaging story of corporate espionage and more.

I can imagine that those who like their sci-fi particularly soft might not dig the crunch of 'Quarantine' quite so much, but I'm confident that even they should be able to enjoy the story otherwise.

I wholeheartedly recommend this book.
Profile Image for Alfonso Junquera perez.
295 reviews8 followers
November 13, 2021
Una novela detectivesca situada en un futuro cercano donde la humanidad ha sufrido un Evento Alienígena, una Burbuja que los aísla del resto del Universo, y que poco a poco deriva en teoría de como la tecnología puede alterar los estados mentales, llegando a eliminar o atenuar los sentimientos, ya por propia elección o impuesto por terceros. Además de eso y por si fuera poco el misterio detectivesco va derivando en una "conspiracion" embarcada en descubrir quien, como y porque se ha generado la Burbuja, y poco a poco ese misterio nos lleva hacia una descripción y elaboración de diversas teorías de física cuántica.
Por lo que he leido acerca de Egan una constante de sus historias es que son un vehículo para poder explicar y desarrollar esas teorías científicas, pero por lo menos a mi en esta novela me ha resultado muy llevadero y entretenido.
Profile Image for Ami Iida.
546 reviews308 followers
January 7, 2016
There are three themes in the novel , it is so called
Dyson sphere , quantum mechanics and nanotechnology.
At the beginning of it the descriptions are drawing
strongly and high technology is written in detail. (less)
Jan 05, 2016 12:57PM · delete
40590836 Ami Iida " Schrödinger's cat" appears in it.
If human being discovered quantum mechanism ,
we could not prosper consumer electronics products computer and ICT.

But at the end of story is boring..................
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