Would the ‘3 Body Problem’ Deadly Nanofiber Web Actually Work?

The new Netflix series 3 Body Problem, like the blockbuster trilogy by Liu Cixin that it’s based on, is heavy on the science part of science fiction. Over the span of the series, we get lessons of varying depths on satellite technology, particle acceleration, nuclear physics, and multidimensional proton compression, the consequences of which we see play out on-screen.

But while nanofibers—the specialty of Dr. Auggie Salazar (Eiza González) in the show and Wang Miao in the books—might not sound like the spiciest corner of 3 Body science, they yield the series’ most memorable scene. Salazar, we learn, has developed an ultrathin nanofiber that is invisible to the naked eye and so strong that it can slice through diamond. As the drama unfolds and tensions with the Earth-bound San-Ti fleet intensify, Salazar’s nanofibers are chosen to strike a blow against a faction of San-Ti acolytes led by Mike Evans (Jonathan Pryce).

Evans and his supporters have made their home—and de facto San-Ti communication hub—aboard a retrofitted oil tanker called Judgment Day that will soon travel through the Panama Canal. Our protagonists choose the canal as the site of their ambush, building a towering web of horizontal nanofibers suspended, invisibly, between two vertical poles.

In the books, the web is called the “zither,” named after the musical instrument that uses a series of parallel strings. We get a few technical details in Liu’s book: The filaments are “about one-hundredth the thickness of human hair,” “extremely sharp,” and affixed every 50 centimeters from the water line to the top of the 60,000-ton ship; the pillars that suspend it are protected with nanomaterial-covered anchors to keep them from being cut down.

The web is raised into place just before Evans’s ship sails through, and as it passes, it seems for a moment as though nothing has happened. Then 3 Body takes us inside the ship, where mayhem is unfolding on every level as Salazar’s ultrathin, ultrasharp fibers slice effortlessly through everything they encounter: hull, engine, wall, and—in a manner that is gruesomely reminiscent of a scene from 2002’s Resident Evil—passengers. The ship crashes into the banks of the canal, with its surreally severed slices tumbling atop each other “like a stack of plates carried by a stumbling waiter,” as Liu put it. The sequence even gets its own ominous bit of soundtrack:

While a lot of the series’ science-fiction technologies, like the super-compressed multidimensional protons dubbed Sophons and the next-gen immersive video game, are explained as belonging to the San-Ti and their much more developed science, the zither is introduced as a present-day Earth creation. Indeed, we see Salazar fine-tuning the creation in her lab and running an early test in which she precisely dices a diamond. Whatever beyond-the-scope-of-human-thought wonders are barreling toward the Milky Way, 3 Body tells us that the nanofibers are achievable with Earth science as it exists today.

Well—are they? Could you cut a container ship into ribbons with a nightmarish, invisible net? Is the real Salazar out there somewhere tinkering with gossamer garrotes? To figure it out, The Ringer turned to real scientists.

Do nanofibers like the ones in the zither actually exist?

Yes—kind of.

Electrospinning is a method of creating nanofibers, which are generally considered fibers with diameters of less than 1 micrometer. Such fibers are relatively commonplace today, says Greg Rutledge, the Lammot du Pont Professor of Chemical Engineering at MIT, who has researched polymeric nanofibers made by electrospinning for approximately 25 years.

“Given that a human hair is about 50 micrometers in diameter, a fiber 100 times smaller would be about 500 nanometers in diameter,” says Rutledge of the threads described in the zither. “Such fibers are routinely made by electrospinning, as well as by a couple of other technologies. Metal wires can also be drawn that small.”

Rutledge ticks off a wide variety of modern applications of zither-like filaments in both organic and inorganic forms: “The usual form in which such fibers are made is random, nonwoven sheets of fibers. A couple of current applications include high-efficiency filtration (HEPA), tissue engineering that mimics the extracellular material in human tissue, and water-repellent fabrics. No zither, but nanofiber technology does exist right now.”

“We just developed a method to make titanium dioxide nanofilaments that are so thin that if you take 1 gram of our stuff and put the nanofilaments end to end, you can go to the sun and back, twice: 400 million miles,” says Michel Barsoum, a distinguished professor in the Department of Materials Science and Engineering at Drexel University. “And this is not science fiction.”

So … could they really slice through an oil tanker?

Alas, Earthlings, they could not. The main problem with the zither is strength.

“​​Any nanofibers when used individually as proposed here would not be much stronger than spider silk,” Barsoum says. “What people do to make them sound more interesting and impressive is divide them by, say, their weight. When you do that and divide by a very small number, the properties look very good. But at the end of the day, the strength is no more than a silk thread.”

“We make the nanofibers from ‘soft matter’ so they are not strong enough to cut anything,” says Paul Topham, a professor at Aston University in the United Kingdom whose research focuses on polymer nanotechnology. There are ways of creating tougher fibers—and they do in fact involve diamonds, just not the way that Salazar’s fictional work does.

“Nanodiamond filaments exist, but actually they tend to be diamond nanoparticles dispersed along a polymer filament,” Topham says. “But if you could make a nanofilament of just diamond, maybe it could do what you are proposing.”

But stroll into the realm of science fiction, and maybe new options will appear, Topham says. “You could say that they are made from a material harder than diamond—from some other planet!—and this could perceivably cut something in this context, i.e. nanodiamond filaments.”

“I think we’d need to find a material that doesn’t exist yet,” Rutledge agrees. “Making it into nanofilaments would probably be the easy part.”

Saptasree Bose, a postdoctoral research student at Northwestern, points to one real-world analogue: Dyneema. “Dyneema is renowned as the world’s strongest fiber, boasting a strength-to-weight ratio up to 13 times greater than steel,” she says. “Its exceptional strength has made it a go-to material not only for lifting and hoisting applications but also in diverse fields such as aviation, marine industries, sports equipment, and personal protective gear.”

Pretend we’ve found this unknown, superstrong material. Would the ship be destroyed as tidily as it is in 3 Body Problem?

Not likely! The book describes the slices of the ship as cut so finely that they are “smooth as mirrors.” In reality, both the ship and the fibers—even ones made of a mythical material that would give them the necessary strength to cut metal—would face peril from a source that goes unmentioned in 3 Body: heat.

“The cutting process would generate friction, which dissipates as heat and causes the temperature of the cutting zone to rise,” Rutledge says. “That could indeed be a problem for a small diameter fiber if the temperature gets high enough to melt or burn it, but maybe the steel would melt first.”

Indeed, one physicist speculated that the temperature could get really high: “However tough the fiber is, if it can’t dump the heat somewhere, its temperature might well rise until it literally ionizes into a plasma.” Plasma is probably not something you want near the hard drives containing records of all communication with the San-Ti, the recovery of which is the point of attacking the ship in the first place.

Rutledge says a possible workaround would be to have the ship travel through the zither “very, very slowly” to give the friction heat more time to dissipate—a major strike against its usefulness in a tropical sneak attack.

Would the zither really be invisible to the naked eye?

“Each fiber could indeed be nearly invisible, especially if the diameter is smaller than the wavelength of visible light, about 400 [nanometers], and one is trying to see them from the bridge of a ship,” Rutledge says.

But even if the fibers themselves were very strong, you’d probably need more than the zither has—a lot more. In the book, we’re told that the zither features one filament strung horizontally every 50 centimeters from the water line to the top of the ship.

“Strength is measured in units of force per unit area, so the strength can be as good or better than larger diameter fibers,” Rutledge says. “The force carried per fiber, however, is proportional to the cross-sectional area of the fiber, so one would need a lot—many millions—of fibers to slow down something as big as a ship, probably a lot more than one every 50 [centimeters].”

Let’s say the San-Ti are real and headed for Earth to wipe us out. Would they really be interested in stymieing research into nanotechnology?

3 Body begins as a mystery: Why have physicists around the world begun killing themselves? Eventually, we learn that they’ve been driven mad one by one by a hovering countdown that only they can see, which the San-Ti have inflicted on those whose work the aliens view as a possible threat if allowed to continue developing. The countdown eventually comes for Salazar, who spends days in a panic before suspending work on the nanofibers that would eventually be used in the zither, at which point the San-Ti reward her by stopping the countdown.

“There are lots of people working on it, and it is going to be big in future advanced technologies,” says Topham, whose work entails designing polymer materials for future tech: “cancer treatment, battery and data storage technology, monitoring brain activity, selectively purifying water, drug delivery, MRI agents, blood salvage devices, and many more.”

Bose sees a future in which nanotechnology could reshape everything from medicine to agriculture to energy—including some areas that fit neatly into a science-fiction mold. “Nano-electronics could lead to faster and smaller devices, quantum computing advancements, and flexible electronics like wearable tech,” she says.

Asked if nanotechnology is an area likely to see much growth in the years to come, Barsoum wrote back simply, “ABSOLUTELY.”

Grade the zither on a scale of 1 (absolute nonsense, could never happen no matter what technological advances arrive in the years to come) to 10 (totally realistic, possibly feasible with today’s tech).

“1.” —Barsoum

“6. Pulling a ship with strong fibers is possible with present technology, but cutting a ship with fiber needs more advancement in nanotechnology.” —Bose

“3. People have already speculated about tethering satellites to the Earth using really long carbon nanotubes.” —Rutledge

“Dare I say 6 or 7?” —Topham