Literature / Death's End

"And now we know that this is the journey that must be made by every civilization: awakening inside a cramped cradle, toddling out of it, taking flight, flying faster and farther, and, finally, merging with the fate of the universe as one. The ultimate fate of all intelligent beings has always been to become as grand as their thoughts."

Death's End (死神永生) is a Chinese Science Fiction novel and the final (official) installment in Cixin Liu's Remembrance of Earth's Past series. It was first published in 2010 and translated into English by Ken Liu in 2016.

Decades after The Dark Forest, the Dark Forest Deterrence has resulted in an uneasy peace between Earth and Trisolaris. Cheng Xin, a 21st-century aeronatical engineer who put together the Staircase Project (a project intending to send a human brain to Trisolaris), awakens from hibernation and befriends Ai AA, an astronomer. When it becomes clear that the dimensions of the universe are nothing like we know and the stability of the entire universe is at risk, humanity must find a way to survive.

The book received a Fan Sequel, The Redemption of Time, that achieved Approval of God.

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Tropes:

• Alien Geometries: Death's End starts with a rather outside-context chapter taking place during the Fall of Constantinople, about a woman who discovered a magic power of being able to move things from behind solid mass. First it was a saint's artifact, and then a man's brain from his skull as proof of her powers. She was jumping into a shard of 4d-space that had intersected with an area of the Earth at that time, foreshadowing future events of that novel, and touching on some plot points that would become major elements of the latestage plot.
• All-Loving Hero: Cheng Xin could be a deconstruction; she is an extremely kind and gentle soul who sees the best in everyone (including people who have tried to murder her in the past), will always attempt a diplomatic resolution and her highest priority is to avoid bloodshed. The only problem is, when the universe is a Dark Forest and avoiding trouble now may cause far worse trouble later, this sort of person may be an absolutely terrible choice to invest with decision-making power.
• Almighty Janitor: The alien simply known as Singer. In comportment with Dark Forest theory, his colleagues don't like or respect him, clearly thinking of him as an unfortunate necessity for their crew as somebody with an unglamorous but needed job, like a plumber or janitor. That said, his job is the Dark Forest strike guy: he scouts for and exterminates entire species.
• And the Adventure Continues: The third book ends with Cheng Xin, Guan Yifan, and Sophon departing Universe 647 to explore a Death World in what's left of the real universe.
• Artistic License – Biology: The peace and complacency of the Deterrence Era somehow resulted in male humans becoming so feminized that Common Era humans can no longer tell them apart from women of the time. Without extensive genetic engineering, which mankind doesn't have, it's impossible for such a profound physiological change to happen within a mere 60 years. Bear in mind that this doesn't just include their looks (which could be explained through surgery and cosmetics), but also their voices. The men then revert back to their Common Era appearance during the Bunker Era, and although the time frame here is somewhat longer (100-200 years), it's still completely unrealistic.
• Ascend to a Higher Plane of Existence: Inverted. Due to dimensional warfare, the universe will keep being reduced to lower dimensions. So higher civilizations must be able to project themselves to lower dimensions to survive.
• Batman Gambit: The conclusion of the Swordholder subplot, started with Luo Ji at the end of The Dark Forest. Trisolarans learned enough of human culture and deceipt that they agree to peace with humanity and share culture and science. While it did trigger something of a Rennaissance within Trisolaris, they cooperated mostly as a long-term plan with the goal to lull humanity into placidity. A vote was held to replace the now centenarian Luo Ji as the Swordholder, the single person who could call in a Dark Forest broadcast, and Cheng Xin, publicly popular and a living symbol of the values of humanity at the time, was voted in. Within five minutes of the handoff, the Droplets attacked, and within ten more, destroyed the Dark Forest broadcast system. Trisolaris was able to do this because they knew that lulling humanity into a sense of security would get them to elect somebody who didn't have the ruthlessness to destroy humanity as collateral damage. Just at expected, Cheng Xin buckled under the pressure and refused to call in the strike when she had the chance. This plan was spoiled by sheer luck: unfortunately for Trisolaris, the last antenna was the hull of the ship Gravity, and it managed to escape destruction of the droplets through the cooperation of the ship Blue Space and a chance encounter with a pocket of 4d-space. Realizing the Trisolarans' plan, they send off the Dark Forest broadcast. It ended the war and doomed humanity, but because they were well within the Oort cloud, their distance from the solar system proper bought humanity a few extra centuries to prepare. Unfortunately, the measures humanity used to shelter against a photoid were anticipated, and what was used for Earth's Dark Forest strike was a much more arcane and fantastically destructive weapon.
• But for Me, It Was Tuesday: Singer's role in the Solar System's destruction, reinforcing the hypothesis that most dark forest strikes are economical and mundane.
• Les Collaborateurs: The Trisolarians found the Earth Security Force (ESF), comprised of over five million human soldiers, to assist in their takeover of Earth, promising them special privileges after everything is said and done. During the Great Resettlement to Australia, the ESF acts just as ruthlessly as their alien masters, attacking humans and their infrastructure wherever Sophon tells them to. Predictably, once the invasion is foiled, the traitors are rounded up and put on trial, with a large percentage executed for their crimes against humanity.
• Cosmic Flaw: The early universe consisted of ten dimensions rather than three, and the speed of light was near-infinite. Unfortunately, over billions of years Sufficiently-Advanced Abusive Precursors have been using incomprehensibly-advanced weapons to create Negative Space Wedgies that are reducing the dimensionality of the universe, and the speed of light itself, to destroy their enemies. Eventually the universe will be reduced to two dimensions, and then one, and then...well...
• Death of a Thousand Cuts: This is happening to the entire universe. With advanced technology, it's possible to lower the speed of light in a region of space called a black domain. One can also reduce the number of dimensions to exterminate everything within it while leaving the rest of the universe untouched. But what happens when you continuously repeat the process everywhere? Eventually these areas chain together to create a universal black domain and lower the universal speed of light. Likewise, it's possible to reduce the number of dimensions in the entire universe through repetition of dimensional warfare. This is how the universe was reduced to current three dimensions from its original ten and well on its way to only two, while the speed of light is reduced to its current speed from its original near-infinite. Eventually there will be one dimension, and then nothing at all.
• Democracy Is Flawed: Cheng Xin's position as swordholder was the result of a completely open and fair democratic process, and she really was humanity's choice for the position. Various characters comment that the fact she was entirely the wrong choice isn't really her fault, but the fault of the decision-makers and the voters who wanted a maternal All-Loving Hero over a ruthless Pragmatic Hero who could intimidate the Trisolarans into playing ball.
• Despair Event Horizon: It's finally revealed just why so many physicists had been committing suicide in the first book: They’d come to understand not only that the sophon lockdown had made further progress in fundamental theory impossible, but also that the ability of Sufficiently Advanced Aliens to casually interfere with their observations called the whole concept of immutable physical laws derivable by experiment and observation into question. As Ding Yi puts it “Do you think only sophons create illusions? Do you think the only illusions exist in the particle accelerator terminals?” This realisation undermines their belief in their profession so badly that it drives some of them to kill themselves.
• Deus ex Machina: The reason why the Trisolaran Batman Gambit against the Dark Forest Deterrence fails has shades of this. Their plan would've succeeded if not for the sudden and unexpected involvement of a fragment of four-dimensional space drifting through the outer reaches of the solar system, just in the right place and at the right time to prevent the complete destruction of the Dark Forest broadcast system. In other words, the only reason mankind survived a bit longer comes down to sheer dumb luck. The whole thing was alluded to at the beginning of the book, but so subtly that it's easy to miss the connection or forget it even happened by the time it becomes relevant later on, making the whole situation feel a bit contrived.
• Diabolus ex Machina: After the few surviving characters have escaped the destruction of the Solar System, and it looks like Cheng Xin and Yun Tianming will finally find love across the centuries, they happen instead upon some never-before-mentioned "death lines," which just so happen to detonate as they're travelling between planets. This so radically reduces the speed of light that relativistic time dilation causes Cheng Xin and Yun Tianming to miss one another by a few million years. Apparently this is the work of life deliberately aiming to hasten the destruction of the universe, also never before mentioned.
• Distant Finale: The conclusion of Death's End takes place 10 billion years in the future, thanks to several cases of Year Outside, Hour Inside, where the last remnants of life in the universe are planning on inducing a Big Crunch to reset the damage caused by Dimensional Warfare.
• The Dreaded: The Trisolarans fear Wade more than they did Luo Ji. They had calculated that Luo Ji had roughly a 91-98% chance (depending on the situation) of transmitting a dark forest broadcast against Trisolaris if deterrence failed. Wade's is always 100%.
• Does This Remind You of Anything?: Sophon makes an offer to humanity. Out of respect, the Trisolarans promise they won't be wiped out when the fleet arrives; instead, Australia and 1/3rd of Mars will be turned into reservations where they can live after the Trisolarans take over, and they even offer to help build more habitats on Mars and in space so the two can species can still live together in peace. The catch is that they'll have no more weapons or heavy industry, and the move to Australia needs to be done within a year. Any humans still outside Australia by then will be considered invaders and killed on sight. The comparisons are not lost on anyone.
• Flat World: The Solar System by the third book, reduced to 2D (which kills everyone in it). Also the eventual fate of the universe due to dimensional warfare.
• Good Is Dumb: Cheng Xin's refusal to endanger human lives leads her to make two Tragic Mistakes that ultimately put mankind in grave danger. It's worth noting that humanity as a whole is far softer and more moral in the Deterrence and Bunker Eras, so they collectively play the trope straight as well. The characters who absolve Xin of personal responsibility for these mistakes do so on the grounds that they blame other people's stupidity for giving such a gentle soul the responsibility to make ruthless decisions.
• Happy Ending Override: Book two ends with the war between Earth and Trisolaris coming to an end, and Luo Ji expressing hope that "one day, bright light will illuminate the dark forest". Come book three, the war resumes, Earth and Trisolaris are both destroyed, and the entire universe is on its way to eternal death thanks to dimensional warfare. Damn.
• Hero of Another Story: Tianming's capture and assimilation into Trisolaran society ultimately commanding sufficient authority and resources that he can order the construction of a pocket universe to gift to his unrequited love could have been a book in itself, but is completely elided. In fact, this inspired a Fan Sequel The Redemption of Time which was subsequently published with the author's permission.
• Hyperspeed Escape: Cheng Xin and 艾 AA escape the destruction of the Solar system by utilizing Halo's curvature propulsion drive. As lightspeed is the escape velocity for the collapsing space, they are the Sole Survivors of the cataclysm.
• Impossible Insurance: Possibly as a Black Comedy Burst, or an accidental one. One of the settlements of the Bunker Era was a research station built around a microscopic black hole. The research head eventually had an episode and threw himself into the black hole; he still existed above the event horizon, compressed down to microscopic size but still recognizably human and intact, and practically frozen in time from an outside perspective due to extreme curvature of spacetime. Even though he was forever lost to humanity, his insurance company successfully argued in court that he was, medically and legally speaking, still alive, so they were able to avoid paying out his insurance policy until he falls past the event horizon, a process which will take untold eons to complete.
• Lightspeed Leapfrog: Trisolaris launches a second invasion fleet, this one equipped with "curvature propulsion drives" that allow lightspeed travel, which will arrive in the Solar system in four years. The first invasion fleet, capable of ten percent of lightspeed, is only halfway there and will not arrive for another two centuries.
• Magnetic Hero: Downplayed, and possibly deconstructed, in the case of Cheng Xin. Her general sweetness to everyone around her and total devotion to the dictates of her conscience (and being very beautiful certainly doesn't hurt), repeatedly cause her to get treated as a borderline-Madonna by those around her. On an individual level this comes out as rapid, profound and uncharacteristic devotion (Yun Tianming, AA, arguably Wade) and on a social scale she gets repeatedly invested with a degree of authority and importance totally at odds with her age, experience and expertise. Unfortunately, this ends up putting her in positions where less likeable, but more hardened, competent and ruthless individuals would have made better decisions.
• Make Way for the New Villains: After spending two books as the main antagonistic force, Trisolaris is wiped out by a Dark Forest strike in Death's End. From there, humanity is left to face civilizations powerful enough to weaponize the laws of physics.
• More than Three Dimensions: Seen in Death's End with Gravity and Blue Space encountering a fragment of four-dimensional space. It's believed that the universe originally had ten macro-dimensions, but this was reduced to three through dimensional warfare.
• Mutually Assured Destruction: The climax of the second book establishes a MAD situation that thwarts the Trisolaran invasion. Applying game theory to the Fermi paradox, the horrifying conclusion is that it's safer to destroy another sapient species rather than risk establishing peaceful contact with them. The analogy is to a "dark forest" filled with armed hunters, in which the safest choice is to shoot first when encountering anyone else - meaning you should avoid announcing your location to the rest of the forest, filled with other hunters who will also shoot first. Couple this with the fact that there are thousands of sapient races in the galaxy, even if they are vast distances apart, and it only takes one of those to shoot a planet-killing (or sun-killing) probe across instellar distances to render you extinct. Humanity rigs up a system to broadcast the location of Alpha Centauri to the rest of the galaxy, though because it's a neighboring star system it would alert hostile aliens to the existence of the Sol system as well. This frightens the Trisolarians into halting their invasion, but they simply wait generations for humanity to grow complacent with peace, accurately predicting that humans who grew up without the constant threat of invasion would be less likely to initiate MAD in a case of I'm Taking You With Me.
  • In a slight uptick in optimism, though casual extermination is the order of the day for most interstellar societies, Dark Forest strikes have to be casual and low cost to justify using them. Singer, one of the crew on a ship belonging to Sufficiently Advanced Aliens, does the duty of finding primitive societies and destroying them with Dark Forest strikes; he's seen as occupying a lower position and as a necessary inconvenience by his colleagues, like a janitor or repairman. There exists means of making Dark Forest strikes impractical, and marking that society as "safe," such as creating a black domain.
• Negative Space Wedgie: A "black domain", also called a "light tomb" and "low gravity black hole" is the use of certain technologies to create a region of extremely curved space, which effectively slows the speed of light within the affected area to about as fast as a person on a bicycle. The affected area is sealed up inside an event horizon: on the one hand, it's an extremely effective protective barrier against Dark Forest strikes. On the other, it's essentially an eternal prison, but some societies feel that their star system is enough, given the risks of dark forest theory. In fact, a society sealing itself up in a black domain is recognized as the universal "safe" signal, since those inside and those outside can't affect each other. They can also be created as defenses: entire swathes of the galaxy are sealed behind chains of these things to form cosmic Maginot lines.
• Noble Savage: Fraisse, an Australian Aboriginal man, is barely characterised beyond his connection with nature, his tendency to offer Cheng Xin kindly words of reassurance, and his fondness for playing the digeridoo. Although apparently having worked as a dentist in the big city before moving back to the outback for a simpler life, Fraisse is very much depicted as the archetypal traditional custodian of the land, not a fully-actualised person.
• No-Paper Future: Inverted. The Earth Civilization Museum stores information by carving characters onto Pluto in order to have it last for geological eons.
• Normal Fish in a Tiny Pond: The Trisolarans are extremely advanced by humanity's standards, having mastered manipulation of the strong interaction force. Yet they're nothing in comparison to the other aliens out there, who are capable of manipulating the laws of physics, lowering the speed of light, and destroying entire dimensions.
• Population Control: The Reservation plan, since it'll involve the loss of industrialized agriculture, will result in mass starvation. Sophon tells them, with four billion humans all crowded into Australia, they'll have plenty of food. She estimates that 50 million humans will survive and form a stable population by the time the Trisolarans take over.
• Punchclock Villain: Singer, the lowest-ranked member of his Starfish Alien crew, whose whole job is to scan for alien civilizations and destroy them from afar (which he often does while singing).
• Sadist: The thing that pushes Wade from being a particularly ruthless Pragmatic Hero into much darker territory is that he explicitly enjoys watching people suffer. To be fair, it is never shown to affect his judgement, and there is no indication that he ever crosses the line into illegal actions or seriously compromising somebody's ability to work (he's too pragmatic for that), but if there's an opportunity to make somebody miserable without compromising their usefulness, he'll relish it.
• Scenery Gorn: The Solar System's dimensional collapse. Every structure and planet is transformed into entirely flat planes in exquisite detail. The Gas Giants become vividly colorful structures resembling tree rings, with everything from their cores to their outer atmospheres visible, and humans spill out into intricately detailed fractal patterns, in a process that is minutely described and captivating to watch in a way that's similar to Scenery Porn. Of course, the process is fatal for all forms of three-dimensional life.
• Screw This, I'm Out of Here!: Several civilizations have decided to skip out the horrors of the universe and wait out its destruction and rebirth by hiding in their Pocket Dimension. This has the adverse side-effect of potentially removing enough matter from the main universe so there won't be enough gravitational pull to trigger a Big Crunch and recreate the universe in its original, unflawed state.
• Small, Secluded World: Universe 647, the gift universe from Yun Tianming that Cheng Xin and Guan Yifan spend some time in toward the end of the third book.
• Star-Crossed Lovers: Though not exactly lovers, Cheng Xin and Yun Tianming. After learning that it was Yun Tianming that had bought the star for her, she rushes to see him only for her to find that his brain had already been removed. Later, when they talk long distance, they promise to meet each other at that star. Much later, when she hears from 艾 AA that Yun has arrived in her solar system, she tries to reach him only to be stuck in the rupture of a death line.
• Story Within a Story: Yun Tianming's three interconnected fairy tales which he tells to Cheng Xin to covertly pass important information to Earth.
• Taking You with Me: Thanks to a MAD signal from Gravity, who decide to take revenge on the Trisolarans now that they're closing in on the Solar System. A photoid is sent by another species at Alpha Centauri, striking one of their stars and frying Trisolaris, while a dimensional strike is later sent into the Solar System and collapses it into 2D space.
• Token Evil Teammate: Thomas Wade. Ex-CIA guy, Cheng Xin's boss and then foul-weather foe, general scumbag; but it isn't personal. He's just a man who's enough of a realist to know what needs to be done, and cold-blooded enough to pursue his goals, damn the morality of it.
  Thomas Wade: "Are you willing to sell your mother to a whorehouse?"
• We Have Become Complacent: Following the establishment of the Dark Forest Deterrence, the Trisolarans' entire long-term strategy for Earth hinges on mankind falling into this trap. They're right. After 60 years of peace in a near post-scarcity society, humans have become so soft that the one they choose to trigger a dark forest strike against Trisolaris in case of an attack proves unable to do so when that attack happens within minutes of her assuming the responsibility. Things go straight to hell from there on.
• Worthy Opponent: Luo Ji is greatly respected by the Trisolarans, to the point they give him the opportunity to ask them an extremely powerful question, and get an honest (though very limited) answer purely because they honour his establishment of the deterrent and the decades he's spent holding the doomsday button. Sophon mentions that they also have this attitude to Wade, who absolutely terrifies them and could have singlehandedly forced them to cooperate.
• Year Outside, Hour Inside:
  • The area in the wake of a sufficiently-powerful lightspeed jump slows down the speed of light considerably, so anyone within will feel time like this. This is how one can signal to the rest of the universe that a planet/solar system is "safe." Cheng Xin and Guan Yifan get trapped in one, spending 16 days in one while eighteen million years pass outside.
  • The flow of time in the pocket universe Yun Tianming leaves for Cheng Xin and Guan Yifan is tuned so that they can survive until the great universe is reborn. They end up exiting after one year, while over ten billion years have passed outside.

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