Complex Numbers

Engage Tractor Beam

Every so often, I'll see an article relating scientific advancement to ideas from science fiction in general and Star Trek in particular. This is one of them.

Star Trek has tractor beams. So do we.  
But so far, they can't grab anything bigger than a dime.

And, like all the rest of them, it's disappointing and ends up increasing, rather than decreasing, misconceptions about physics.

Like, a while back, there was a slew of articles about teleportation. Of a single particle, but with all the hype attached to it, I'm sure people thought transporters were just a few years away.

Spoiler: they're not.

This is similar.

The “tractor beam” has been a reliable narrative device in science fiction for nearly 100 years, deployed whenever the plot requires seizing a runaway spaceship or manipulating objects at a distance.

That's right; Trek didn't invent the concept. As an aside, as a kid, the phrase "tractor beam" in Trek confused me. Being on a farm, I knew damn well what a tractor was. It was only later, after four years of Latin in high school, that I finally figured out that it comes from the same root as "attractor."

Okay, maybe it didn't take me that long, but remember, I started watching Trek at a very young age.

Anyway, the root, trahere, means "to pull," and we can already do that mechanically, or with magnets.

But most sci-fi fans probably know it from Star Wars and Star Trek — the sinister Death Star and the mighty USS Enterprise each boasted a frequently convenient tractor beam system.

Ugh.

Star Wars is great, too. I don't take sides. What I do insist upon, though, is that Star Wars isn't science fiction; it's fantasy with SF props.

The first thing to know about real-life tractor beams is that they work more like another sci-fi concept: force fields.

No. No, they really do not. As the article explains, it's sorcery with light and sound waves. The completely fictional idea of force fields is about energy without mass. One could argue, of course, that creating a barrier of focused sound waves would do a lot of what a force field is supposed to do; that is, keep people and things from crossing it.

Anyway, look, I'm not knocking the science, and I'm only knocking the article for being a little misleading up front; the author does go on to explain the technology in some detail (without getting too technical). As the author points out,

We won’t be using tractor beams to yank around Corellian-class smuggling ships, but we could certainly use them to accomplish touchless manipulation of tiny objects in places where precision is at a premium.

The abdominal cavity, for instance. Subramanian says that in the future, acoustic tractor beams could be used to move tiny nanobots inside the body for targeted drug delivery, when a particular medicine needs to be delivered to a particular area of tissue.

That seems to be a very niche application, but I think it's an important one, and pretty cool.

Drinkwater concedes that it will be “a fair few years” before any of this happens — and many more before we can start scaling up to spaceship-sized tractor beams.

Yeah, more like centuries for the latter, absent some sort of massive breakthrough.

Just don't expect to see these at your neighborhood Tractor Supply Store.