On "The Three Body Problem" and 'hard' sci fi
A review of sorts, but also a critique of 'hard' sci fi snobbery
Overall Rating: ★★★☆☆ (3 out of 5)
Science Fiction: ★★★★☆ (4 out of 5)
Literary: ★★☆☆☆ (2 out of 5)
Vibe: ★★☆☆☆ (2 out of 5)
[No spoilers section]
In setting a goal to write my own sci fi novel, I thought it’d be good to read (or re-read) some of the works that loom large in the genre. Up first is The Three Body Problem by Liu Cixin — in part because a free TV series recently became available on YouTube and apparently there’s one coming out for Netflix.
I've never particularly liked the “hard” sci-fi distinction in the genre as there are almost always a couple of completely fantastical elements in novels (or films) with respect to science. There's also been what seems to be a degeneration to a simplistic “hard sci fi means no faster than light travel” — at least in my subjective experience. The Three Body Problem respects Einstein's speed limit (for the most part!) — however, it takes liberties with much of the other physics (as well as the sociology of physics) [the spoiler section below has examples supporting my thesis that “hard” sci fi isn’t a meaningful distinction].
To me (and this is totally my opinion here) there are three major groups: fantasy (Lord of the Rings, Dragonlance), science fantasy (A Wrinkle in Time, Star Wars), and science fiction (2010, Star Trek). The first generally ignores science and technology for magic or supernatural entities, the second has superficial elements of science or technology, while the third brings science and technology to the forefront. If it makes something up — and it almost always will — it at least tries to have an explanation. Sure, there’s a great deal of level-crossing going from aggregated categories to specific works — the meaningful degrees of freedom change (see here for an example of how I think about this kind of generalization).
Trying to distinguish between “has an in-world explanation in the author's notes”, “devotes a paragraph to explaining each new technology”, or “has entire chapters of fake science exposition” is cutting the category too fine in my opinion. If “hard sci fi” is restricted to plausible technologies that are bound by the current known laws of physics then we're basically stuck with cyberpunk on Earth since doing anything besides having a person travel to Mars to survey some rocks is basically out of the question without breaking a few rules. And cyberpunk on Earth is great! But I think science fiction is about exploring much more varied ways of living.
In fact, I'd turn my classification on its head. Science fiction is about exploring human nature given a coherent perturbation to human society — plausible technology or fictitious science are only tools. The more plausible the science, the more limited the rule breaking — the “harder” the sci fi — the smaller the perturbation to human society and the more limited the exploration. It needs to perturb the system just enough to encompass the ideas you want to explore — the best do it exactly enough and no more.
In that sense, The Three Body Problem is excellent. I don't really agree with every detail of the primary perturbations or the consequences (in particular the reaction of physicists; more below), but they are coherent and concise. The best parts of the book are the themes incorporating striking parallels or almost Bach-like inversion. For example, there are two extended passages that are almost identical in structure with the entire context inverted reminiscent of Godel Escher Bach. Factionalization and different reactions to or views of symbols play out at multiple scales from full through-lines in the book down to single scenes.
I found the fake science exposition entertaining (many points I would think to myself “this is a pretty good pedagogical approach”), but also at times kind of dorky for lack of a better word. It would be risibly pretentious if it weren't so earnest. It's hard to pull off and Liu's earnestness makes the whole book seem like an extended metaphor or an epic fable. The combination of an earnest love of science and scientists with the darkness of the view of human nature seems like it should be in tension. It appears as two sides of a coin, but not much is made of it without feeling like you might be reading too much into the source material.
It’s definitely, as many reviewers put it, a “new classic” in the genre — albeit one with flaws (see below).
[Spoiler section]
One thing that I've seen in various reviews is that the characters are thin and mostly serve as devices to explore the themes and move the plot — and I'd basically agree. Ye Wenjie is the least one-dimensional character, but has more of a character line than a character arc experiencing a few losses: her father's death in the cultural revolution, a betrayal out of cowardice that doesn't have any lasting impact besides getting her to Red Coast which she appears to like, the death of her husband which she causes out of a rational self-preservation motive. She takes the first two of those losses hard and decides to take revenge on humanity. In addition to the portrayal of sexism in the book, I can’t help but think this represents a manifestation of it in the same way Eve’s “betrayal” manifests the sexism of the cultures the story rose from regardless whether Liu’s reference is intentional. Almost all of the women in the book have hidden agendas and act out of emotion, while the male characters (including the protagonist) are earnestly trying to do their jobs and logically figure out what is going on. Making the women extremely effective super-geniuses doesn’t make up for it, and may even exacerbate it — remember that Eve ate of the tree of knowledge.
As a side note, Liu’s portrayal of environmentalism appears almost conservative — all flawed humans that would betray individuals or civilization in favor of every other species and their own personal issues. Some men will destroy humanity instead of going to therapy.
Wang Miao and Shi Qiang's friendship is built up better in the TV series — likely because the non-verbal communication the actors brought to the material. In the books, I'm not really sure they are friends. Wang's wife is basically forgotten about and the book might have had an interesting take on what the events Wang is experiencing do to his personal relationships with people that aren't witnessing them. Mostly the people “out of the know” fall in to two classes: 1. named characters seeking to be in the know and 2. just an impressionist background to let you know the world doesn’t just consist of characters in the know/seeking to be in the know.
Given the thin characters, the book seems to be trying to be more an epic fable than a complex human drama — the ideas are more important and the scale we focus on is the society and its perturbations. Individuals are just agents for those perturbations; the book is operating at the higher level of abstraction where e.g. polycrisis might make sense as an emergent concept.
As a random note regarding the TV show — for the most part it is extremely faithful to the source material with a dedication that I have not seen before. However, the series completely changes the crew of the Judgement Day to be literal serial killers (even, say, the cooks and mechanics), possibly to avoid some aspect of Chinese state media censorship that (reasonably!) abhors the murder of innocent hired hands1 in the pursuit of a utilitarian goal of getting information that may help humanity survive. This makes this episode so ridiculous (especially because of how faithful the rest of the material is) that you should just fast forward to the CGI visualization of the ship being sliced by the zither — it captured exactly what was in my head.
As I mentioned above, I wanted to delve into the hard sci fi distinction a bit more with spoilers — there are several ideas that make my point that even “hard” sci fi has fantastical elements; what matters are what those fantastical elements do for the story.
The discussion of dimensions with regard to the sophons was hard to follow for me as a physicist. It seems to be a reference to the 10+1 dimensions of M-theory2. The chapter is an entertaining short story on its own, but I might even cut it if I was an editor and this was a one-off book (I imagine it lays groundwork for later books which I have not read). The thing about different dimensions in physics is that they are often just alternate representations that make calculations more sensible, or in string theory required to cancel anomalies (failures of classical symmetries to survive quantization). That is to say they're not different universes and "unraveling" a proton into a lower or higher number of dimensions that somehow exists in our 3D space is pretty much completely artistic license. The compactified dimensions (e.g. Calabi-Yau space) in string theory are a way to have the universe be 3+1 dimensional at our size (length scale ~ 1 m), but 10+1 dimensional at the scale of a string/Planck scale. At the string scale (assuming string theory/M-theory is correct!) the universe is 10+1 dimensional while we humans experience an "effective" 3+1 dimensional universe.
There are genuine approaches to the physics of the structure of a proton that involve different numbers of dimensions — the one that comes to mind from my own work is a workshop at the INT when I was in grad school on string theory and QCD. The AdS/CFT correspondence was only a few years old and one idea was "AdS/QCD" — that you could find a weak gravity theory on an AdS space in 5 dimensions that would help you understand the low energy behavior of a 4 dimensional (3+1) approximately conformal gauge theory QCD on its boundary. The proton is a low energy state of QCD where the equations are basically impossible to solve; at high energy, the theory is effectively “free quarks” that is relatively easy to treat mathematically. The idea is that the strongly coupled QCD at low energy has an easy description in terms of a weakly coupled gravitational theory in a different number of dimensions — but also a “dictionary” directly mapping the states in one theory to the other.
However, I think the idea Three Body is exploring is that the understanding of the fundamental structure of matter through experiment is the key to scientific advancement — something that brings the particle physics, nanomaterials, and sophons into a coherent framework. That is good writing (in terms of idea content3).
So in a sense what I am saying is that the idea of “hard” sci fi is somewhat audience dependent. I am a physicist with a thesis on the quark structure of protons and who has some string theory background. To me, the whole sophon thing in terms of the science is not very different from the science fantasy of Star Wars. The real difference is that Liu cares about science and tries to invent a world with explanations that go on to perturb human society, which makes his work science fiction instead of science fantasy. However that is really the only distinction and caring about physics or caring about psychology or caring about economics all fall under the heading of caring about science.
The purported mechanism for sophons producing patterns in the retina would either involve tremendous amounts of bremsstrahlung or be too slow to produce a readable character. However, this aspect of the sophons was far more believable (for me) as a driver of despair than particle experiments not working. Unexplained results in an accelerator experiment would actually be exciting to physicists! The problem since, say, the 90s has been very little deviation from the standard model. Even the Higgs discovery was basically just another standard model confirmation. Accelerator experiments where weird stuff started happening would be met with enthusiasm.
Liu also has a different view of the relationship between theory, experiment, and application in physics from my personal experience. His take seems to be that experiment is always at the forefront and applied researchers don't have a basic understanding of theory.
In physics, there is a “division of labor”; in high energy (particle) physics there's even a formalization of theorists, phenomenologists (those who connect theory and experiment), and experimentalists in separate arXiv sections if not actual work. However even applied solid state physicists (the kind Wang would be given he is working on nanomaterials) will have a great deal of knowledge directly related to particle physics. Modern formulations of the structure of matter are basically quantum field theories with excitations that can be more complex than standard model field theories due to the more complex symmetries that can exist due to a material's atomic structure. There are several points where I was like "Dude, did you forget grad school?"
The actual relationship between theory and experiment tends to be dynamic in the history of physics — sometimes theory is “out front” (e.g. recent decades where accelerators have turned up little), sometimes experiment is “out front” (e.g. the decades preceding quantum mechanics where theory couldn’t explain experiments). In particle physics these days, experiments are (usually) expensive while theory is “cheap” — there tends to be large amounts of the latter produced that would potentially get culled by experiment. And most experiments are working to test or rule out at least some kind of existing theory. That's how they generally get funded!
In addition, particle accelerators are not the only way forward. There are several experiments that are just watching a tank of something (usually water, e.g. Kamioka). The leading order temperature of the frequency distribution of the cosmic microwave background is well established4, but a lot of science is done using the anisotropies. The entire universe acts as a particle accelerator and cosmic rays achieve energies far higher than any terrestrial accelerator (the drawback is low luminosity). Given 400 years until the trisolarans arrive, there could be enough data from just watching the sky.
Again, this is fine for Three Body as an epic science fable. The sophons can probably figure out a way to magically block these other avenues as well. The point I am continuing to make is that even purported “hard” sci fi can be shaky if inspected closely enough by knowledgeable people. It's just a matter of degree, not kind — and it becomes a socio-economic reason (i.e. that our society only trains a limited number of particle physics Phds for perfectly rational reasons) your novel is achieving its “hard” sci fi designation that gives way to snobbery.
In my work on Inner Horizon, I am literally finding references for nearly every weird idea I'm putting in the book. However, I also recognize that, per my “cyberpunk on Earth” comment above, I have to make at a few implausible leaps to make it interesting. One of those leaps is not entirely baseless [pdf]:
I'd imagine that because of the dedication to hewing close to recent work in theory, Inner Horizon would get a “hard” sci fi designation5. It still could be picked apart by actual experts — even relative novices such as myself! And I imagine Liu himself would note at least some of the things I pointed out above with respect to Three Body. But in both cases, I'd just call it sci fi.
Next up will probably be Ursula K. Le Guin’s The Dispossessed or Greg Egan’s Diaspora neither of which I have read before.
Some other random observations. I want to note that these are mostly to support my claim that even purported works of “hard” sci fi take significant license with science — to the point where the “hard” sci fi designation is pretty meaningless.
Entanglement does not allow superluminal communication (and once “read” the entanglement generally disappears although there is subtlety here regarding quantum eraser experiments which requires control over both parts of the entangled pair). However, I think this is fine as a narrative device that really plays only a small role in The Three Body Problem.
The strong nuclear force would be a different theory in 2+1 dimensions with no particular relation to the 3+1 dimensional theory of quarks and gluons (quantum chromodynamics aka QCD). This is meaningful because the strong coupling constant g² is unitless (i.e. just a number) in 3+1 dimensions so "dimensional transmutation" creates the mass scale of QCD through the beta function (i.e. the theory has a conformal anomaly that breaks a classical symmetry). In 2+1 dimensions, g² has units of mass so the theory has a mass scale already. However, if we've already suspended disbelief with regard to the unfolding there's no real problem taking it further creating “strong force circuits” analogous to electromagnetic ones. QCD does have non-linear self-interactions but guessing a society that developed in a non-linear solar system might have special insight.
There's not enough antimatter in the interstellar medium to accelerate a vehicle of any appreciable size to any o(1) fraction of the speed of light. This has just a bit more of a hi-tech feel than, say, nuclear explosion powered spaceflight so I'm fine with it. It’s basically the Bussard collectors from Star Trek.
The alpha/beta/proxima centauri system is more a binary with a very small, distant red dwarf companion (proxima) so isn't so chaotic a system on the short time scales of civilizations. However — and this is an example of a great choice of “bending” science for good sci fi — the idea of science extracting the regularities of nature being a source of progress is the central theme the book is exploring. Making this extremely clear by making the system chaotic on a scale comparable to the history of civilization on Earth makes it far more relatable to humans reading the book than, say, having the system chaotic on an evolutionary timescale where you get to bacteria in one cycle and flowering plants in another.
I am not sure how any aspects of prior civilizations could survive a condition where tidal forces rip the planet apart and create a moon. The heating involved with just small tidal forces is enough to make Io one of the most volcanically active systems in the solar system. Generally water would be stripped away from a planet that has no magnetic field, so the core of the trisolaran world would have to be fluid enough to support currents which means that being ripped apart would turn the surface to lava. Not many chemically complex structures (aka life) could survive. The age of the alpha centauri system is several hundred million years older than our solar system so could probably have one or two such events that send the planet back to the primordial soup — but not a recent one.
Makes me think of the whole “contractors on the second death star” discussion in Clerks.
Physicists will talk about 10+1 or 3+1 dimensions where the +1 “time” dimension is treated as a different kind of dimension from the spatial ones. Mathematically, this translates into the SO(3,1) group of rotations and boosts that make up the Lorentz symmetry group.
Since I cannot read Chinese, I cannot comment on the writing as art. I know translation of art is a really hard task (my personal experience where I can read both languages is in Spanish; thinking here of translations of Borges), and Ken Liu created a great one that appears to have captured much of the nuance.
It should be emphasized that the 2.7 K temperature is actually a (defining) property of a frequency distribution; the book makes it seem like the cosmic microwave background is a specific microwave frequency — almost like a spectral line. However, it is a thermal distribution made up of many frequencies.
If I meet my goals and actually finish it.