The 5 Coolest Technologies from Hard Science Fiction

Like most of Stephenson’s books, The Diamond Age is as much an exploration of technology and human society as it is a story. In this case, the focus is on molecular nanotechnology and the titular Primer, which is an iPad-like device that integrates nanotech and an uber-powerful AI.

The Primer imprints on its user when it’s picked up and immediately begins teaching them whatever they need to know in order to become a functioning, self-sufficient member of society—as well as how to survive and adapt to nearly any situation. What makes the Primer especially useful is that it senses the user’s surroundings, mental state, and personality, then communicates its lessons in a way that the user can understand.

We haven’t reached the nanotech mastery of the "Diamond Age” (so-named because it marks the period when humans can literally assemble diamonds from carbon atoms), but we’ve gotten pretty close to achieving the Primer: the One Laptop Per Child Foundation handed out tablets to Ethiopian children in order to teach them basic reading skills (among other things), and the children soon taught themselves how to recognize letters, spell words, and more. The foundation’s project was directly inspired by Stephenson's primer.

By Robert Heinlein

Robert Heinlein's Starship Troopers didn’t invent the space marine trope, but it sure as hell cemented it. Here’s how the soldiers’ exosuits are described in the book:

“Our suits give us better eyes, better ears, stronger backs (to carry heavier weapons and more ammo), better legs, more intelligence (in the military meaning...), more firepower, greater endurance, less vulnerability … Suited up, you look like a big steel gorilla, armed with gorilla-sized weapons.”

Though full-body mech suits aren’t here yet, we’re making progress: the US has unveiled plans to create an Iron Man-like powered exoskeleton called the TALOS suit, and Russia recently revealed their own powered suit with a high-tech HUD and body armor.

Going forward, the biggest challenges for powered exosuits will be similar to the challenge of engineering battle mechs: balancing the strength of materials against their weight and figuring out how to power them efficiently. As for better eyes, better ears, and more intelligence, DARPA's "Squad X" program imagines soldiers equipped with small, high-tech kits networking with drones and other robots on the battlefield to share data seamlessly. According to Deputy Defense Secretary Bob Work: “Ten years from now, if the first person through a breach isn't a robot, shame on us."

Poul Anderson

Originally proposed in 1960 by physicist Robert Bussard and made famous in Tau Zero, the Bussard ramjet creates a miles-wide electromagnetic field that acts like a net to collect free-floating hydrogen, then funnels it into the central engine, where it’s compressed until it creates fusion. The energy created from nuclear fusion is then ejected from the engine and creates thrust.

Here’s the cool part: instead of carrying fuel with it (which slows it down and requires refueling), the ramjet collects fuel as it goes, and if all that matter can be harnessed efficiently, then the spacecraft can accelerate to ludicrous speeds—potentially allowing human passengers to cross the entire universe within one lifetime.

Various scientists have pointed out that Bussard’s original concept has some major flaws, but they’ve also come up with some fixes: first, there’s not as much hydrogen floating around the universe as Bussard imagined, meaning that getting a ramjet going would require starting out in a nebula or similarly hydrogen-dense area. Second, the proton-proton fusion method Bussard imagined is way too weak to create enough thrust, but there’s another method called the CNO Bi-Cycle that would work better.

However, because the ramjet’s engine relies on nuclear fusion (and research funding is spotty at best), it’ll probably be a long time before it becomes a reality.

Arthur C. Clarke

At 22,400 miles tall, the space elevator in Fountains of Paradise is mind-boggling in scope, but from a logistics point of view, it makes a lot of sense: instead of spending $22,000 per kilogram to launch material into space, a space elevator could do it for “just a few dollars,” according to NASA’s David Smitherman. It’d be reusable, fast, and available for continuous use. From a practical point of view, though, space elevators are still on the fringes of feasibility.

As explained by Hank Green of the SciShow, there are three major components to a space elevator: the anchor, the cable and the counterweight. The anchor point would ideally be on the equator, the cable needs to be at least 21,750 miles long (ideally, it’d be 62,000 feet long), and there needs to be a sufficiently heavy counterweight attached to the other end to keep the cable taut (probably a captured asteroid).

To create a cable of that length and strength, pretty much the only option is carbon nanotubes, which have been revealed to be a much trickier substance than previously thought: if one atom is out of place within the tube, its tensile strength is reduced by half and the whole thread can rapidly unweave itself, leading to a catastrophic failure. Based on how long it takes to manufacture high-quality nanotubes in quantity, it could take years to produce enough to create the cable. Right now, one of the more optimistic estimates for a full-sized elevator (according to the International Academy of Astronautics) is 2035.

By Kim Stanley Robinson