By Greg Egan
I got this from the town library and read it over the course of February and the start of March in 2024. An absolutely unbelievable selection of 20 or so stories, packed with hard sci-fi and dealing with the frontiers of physics, maths, neuropsychology, and biochemistry, with a healthy dose of philosophy about the role of the self in a world where we can directly alter the brain with precision.
Here’s a brief summary and review of the stories.
Classic conceit in an interesting setting: everyone has a jewel, a crystalline computer, embedded in their head, which is tweaked to exactly mimic your brain over 25 years. Then, the brain is removed and the jewel left to control your body. The narrator is consumed with paranoia about whether he is the jewel or the brain - by the end of course it turns out he is the jewel, but not before he endures a period of months locked into his own body when the brain and jewel become accidentally disconnected.
A man whose wife is murdered decides to take a temporary implant which temporarily alters his conception that life is valuable. Of course, once he kills the murderer, he finds the sense of conviction he has irresistible, and makes the implant permanent. An interesting exploration of a world where specific directed electrical and chemical signals can alter such high-level concepts as the value of a life.
A wife whose husband is in a bad car crash is told that the cheapest way to keep him alive (and therefore the only one her insurance will cover) is to implant his brain in her womb for two years until a new body is grown. It examines how she bears the disgust she feels, and how that permanently changes both her relationship with him, and her own self, killing her in a small but significant way,
A future civilisation created a wormhole to extract the past’s flora and fauna for study. Unfortunately, it became unmoored, slipping over spacetime and the surface of the Earth. The entry to the wormhole is a huge sphere a mile across, and the exit is a smaller sphere at the centre, displaced in time by a femtosecond.
The narrator acts as a runner, entering the wormhole to save those within it from its relativistic effects. The key one is that since time and the radial dimension are swapped, it is impossible to go further from the centre of the wormhole: all futures lead in, much like a black hole. This has effects on human biology and psychology which mean you can’t stay in for too long. Another is that you never seem to reach the black sphere: it perpetually recedes from you, since light can travel in but not out.
When saving a lady, the narrator sees a blue crystal in the air. Suspecting this is the navigator of the wormhole, he shoots and destroys it, hoping that this will unmoor it from Earth and prevent it from killing people. However, when he reaches the centre and it stays much longer than before, he suspects that the navigator was actually trying to move the wormhole (rather than keep it in one place, as he suspected). He, and everyone else at the centre, may now be trapped there.
It had a really brilliant bit about the counterintuitive nature of half-lives. The wormhole has a half-life of 19 minutes. Therefore, at all times inside the wormhole, you always have a 50% chance of living for another 19 minutes. The probability never changes.
A story very similar (I thought) to the memetic ideas of qntm. At some point, an event takes place which causes people’s underlying beliefs to be sensed by and indeed influence others. These encompass beliefs like religion, solipsism, ethics, and so on. While the initial stages are chaotic, the long-form behaviour is that human society now maps out a phase space of beliefs, forming attractors and people in orbit around them.
Stable attractors are congregations of people who have the same beliefs, whether because they started out with them, or they fell into the attractor and were influenced by them.
The main characters are on chaotic orbits between the attractors, treading the paths between the basins and being influenced by them one after the other, but never captured. They are looking for a way out of the city into the wilderness, where the population density is so low that they can live in freedom. However, a stranger explains, if their orbits were destined to leave, they would have done so already. It’s far more likely that they are in fact caught in their own, strange, attractor, forever treading out chaotic orbits which never repeat, but trapped nonetheless.
An unbelievably cool and rich idea, and this is one of my absolute favourite stories, influenced of course by the Chaos short option I did.
This is another story set in the world of Learning to Be Me, but a different character. A man is obsessed with the idea that it is impossible to ever truly know how another person perceives the world. He keeps trying to understand his wife through various means, by (as the technology becomes available), swapping bodies with her, swapping into new bodies which are twins, and eventually, signing up to an experiment which temporarily tweaks their jewels to be exactly the same (halfway between) and spending eight hours in identical bodies in identical rooms.
Afterwards, of course, they retain all their memories of their time as one person, and the prospect of spending the rest of their lives together is exactly the same as the prospect of being alone forever. And so they break up.
A more slow, philosophical piece on the question of qualia, and whether we would even want to experience the world the same as someone else.
The story is included in the linked page.
A slightly more confusing story, closer to The Garden from TIHYLTTW than anything else: it explores a world where biochemistry is almost a solved science, with drug lords being able to use molecular construction techniques to design drugs to affect neurochemistry more accurately than ever before. The plot, of an agent chasing a researcher who defected to a region in South America controlled by cartels, is more to carry the ideas than anything else. One of the weaker stories, but still very interesting.
Perhaps my favourite story of the lot. What if maths, instead of being some platonic ideal that all matter follows, is instead continuously created and tested by matter? What if, in the moments after the big bang, matter was creating our arithmetic simply by virtue of interacting with itself?
The natural consequence is that other regions after the big bang, located a spacelike interval away, would decide upon different arithmetic. In the present day, two researchers find a defect, a contradiction in maths, where one result is from our maths, and the contradicting one is found by using maths from the other side.
A financial company intends to use this to game the markets, and so they sign up to time on a supercomputer to try and map the other side and seal it off. However, when they eventually decide this is not enough and they need to destroy the other side by proving results incrementally from our side, something fights back. It turns out that the other side of course defines an entirely different universe, which cannot be interacted with except by observing the results of mathematical theorems.
Since the other side is defending their maths, there is no longer any danger in leaving the defect as it is. An unbelievably interesting story with really cool ramifications, explored in the sequel later on.
A commentary on the post-scientific generation, represented as a world with a pandemic of the so-called Silver Fire which encases humans in layers of their own skin which becomes disconnected from their bodies, leaving them immobile and in unbelievable pain.
A researcher notices a pattern of infections and goes to investigate. It turns out that there are people who believe Silver Fire is a blessing from nature, and that it should be spread. The thesis is that the ideas we take for granted, of a scientific world lacking spirits and naiads and gods, as opposed to the intuitive notion of a motive agent controlling nature, is hard-won and took effort. Our kids, who will grow up in a world where this is the default, have no idea of the effort it took to get these ideas, and reject them in favour of spiritualism. A really interesting idea that perhaps doesn’t allow for the crackpots existing in every generation, but which is plausible nonetheless.
An exploration of happiness and what it means to us. A young boy develops a tumour in his brain which floods him with neurotransmitters making him happy all the time. Eventually, a treatment is developed to remove the cancer, but it accidentally also targets all the receptors for the feel-good neurotransmitters, leaving him unable to ever be happy or feel any positive emotions.
Decades later, a novel treatment is developed which embeds circuitry in his brain to artificially restore those receptors. The new receptors are an amalgamation of those from several thousand donors: thus, at first he likes and derives happiness from everything. However, in an effort to restore his own personality, he starts to control what gives him happiness, to develop a sense of taste. He gets a girlfriend, but to do so he has to consciously choose someone to like, and manually increase his feelings for her.
When he tells her this, she leaves. At the end, he reflects that really, his situation is no different from everyone else’s: our likes and emotions are half influenced by genetics and other things outside our control, and the other half are reinforced or removed by our conscious decisions. His is just more direct.
A more philosophical piece about happiness and its role in our lives, saying it is more arbitrary and meaningless than we think, and that the importance we place on it is very much a remnant of our animal origins.
A story that raised more questions than answers, but with a deeply empathetic view of religion. In the distant future, another planet has been settled from Earth: Covenant. The exact sequence of events is unclear, but a woman named Beatrice seems to have cut off links with Earth, and convinced the uploaded minds on the spaceship to reincarnate and become mortal again, whereupon she crashes the ship into the ocean. To the religions on the planet, she is a saviour figure, whereas to the novel scientific movement, she is more ambiguous, but certainly important.
The narrator jumps into the sea as a child, and experiences a religious moment which converts him immediately. He carries a sense of euphoria with him for his adult live, whenever he thinks of Beatrice. However, in the course of his studies of the oceanic microbiome, he sees work proving that the excrement of a certain type of bacteria can cause euphoria in people exposed to it. He realises that this was what caused his religious experience, and, disillusioned, has to learn to live without her presence.
Many of the questions are left unanswered, but nevertheless, a beguiling read. The worldbuilding is particularly cool: the manufactured nature of all life on the planet leads to things like living ships which swim via ion movements, and a transferable penis which deeply affects relationships in their society.
An alternate-universe retelling of the story of Alan Turing. The character in this universe is rescued from his “therapeutic” torture at the hands of British intelligence, to stop him being gay, by a traveller from the future of an alternate universe. Together, they try to rapidly ramp up the rate of scientific development in that universe’s 1950s and 60s.
However, the equivalent of CS Lewis believes he is being influenced by the devil, and tries to stop him. It culminates in a televised debate on whether machines can truly think or not. Soon afterwards, the Lewis-alternate, whose wife is dying, is visited by himself from yet another universe, who tells him that his wife is alive and well there, and that he should join them. Believing them to be the work of the devil to the last, he rejects the apparition, and rejoices in his strength.
An elegy for the victims of the repressive regimes of the past, and an exploration of how religion and belief alters the understanding of the very same facts.
On a couple who create an artificial child who is the only being in existence who does not split in different universes. I didn’t fully read this, it was a little boring.
A continuation of Luminous, above. The characters have now developed a way to communicate with the inhabitants of the far side, by modulating the result of a particular theorem. They develop a new technique to “convert” theorems from their side into ours, by derivation using physics rather than having to brute force from the edge. They can also begin to map the solar system of the far side, by watching theorems often calculated by physical processes, using the internet to develop a kind of radar.
Despite the truce, it is easy for either side to attack the other, and so they attack us until we retaliate with the new technique. Financial systems are the first to drop, followed by complex electronics like laptops, servers, newer cars, and the entire internet. Eventually a truce is called, and we decide to seal the border, as well as nerfing the new technique, losing all contact with their world.
SUCH an interesting idea and I really liked this story.
A riff on the idea of artificial intelligence. A billionaire develops a chip capable of calculations orders of magnitude faster than anything else. He develops a new form of life, and artificially evolves it, managing environmental pressures, over millions of years of computer time, until they develop rudimentary intelligence. He gives them the ability to self-modify, and immortality, but removes their ability to have children, giving them a goal to aim for. Eventually, when they are smart enough, he gives them access to a laboratory in the real world, and tells them to gain experience so they can help him. Unfortunately for him, they are aware of their fragile state and exploit newly discovered nuclear physics to escape into a pocket universe.
A fascinating idea, and very similar to, among other things, that one Rick and Morty episode, and the short story about an AI developing GR from just a few frames of video.
A story about a young chemistry prodigy in Iran developing a superconductor, and her struggles to keep control of the discovery and get patent rights via an economic scheme. Less about the science and more about the sheer difficulty of making any scientific progress in such a situation.
A story about a woman who is woken into a world where gravity now points east. Quickly realising the unphysical nature of this (in perhaps a too-exposition-heavy scene) she is told that actually, she is an amalgamation of thousands of people, reincarnated as an NPC for a set of VR games. She decides to make the best of it by exploiting the game engine to make a life for herself.
A little exposition heavy, and a little meandering, but the concept is great and the characters are well fleshed out. It continues in a much more interesting way in the sequels.
A story about an actor who creates an artificial clone of himself with about 70% of his personality, and how the clone has to deal with both the hidden past, his lack of legal personhood, and how to deal with the legacy. Most of the story is less about the science and more about the actor’s history, of giving most of his money to his husband’s sister for her cancer treatment, and of a major deal which is stolen from him. A little touching, but overall a bit meh.
A continuation of bit players, where the characters can now exploit a vulnerability in the GPU renderer to skip between VR games, looking for one where they can be free. Eventually, she gets to the world of 3-adica, where geometry follows the rules of p-adic numbers, and has to navigate it.
Most of the story is a fascinating exploration of what life would be like as a game character: what agency there is, the unwritten rules, and the tyranny of the game engine. The 3-adica exposition is a little boring and hard to get around, but the rest of the story is worth it.
The final part of the bit players series, where the characters learn they will be shut down in a resource squeeze. They decide to exploit vulnerabilities in a particular brand of VR headset, and make contact with a player who is convinced that her dead grandma has been reincarnated in the game as one of the NPCs. Through her, they escape into the internet and can continue to live while they attempt to get legal recognition. Perhaps one of the weaker stories, as the subplots about the Vienna Circle and random bits of number theory are a bit aimless.