[♩INTRO].

Science fiction is amazing, although the technology in it often seems a little more fiction than science. But some of the most far-fetched ideas might be more realistic than you think.

Take force fields, for example. We may never be able to build ones as perfect or impenetrable as you see in movies, but we might be able to make something pretty close. And some teams are already working on it.

The details vary depending on the series, but typically, force fields, sometimes called energy shields, are nearly invisible barriers that block matter and radiation. They can be used to protect a spaceship from lasers or cannons, or just to confine a prisoner for a few hours. But in the real world, most teams working on energy shields are doing it to protect military vehicles.

The research is broken into two categories: fields that block matter, and those that block radiation. Surprisingly, we’re actually making more progress on the ‘block matter’ side. The UK’s Defence Science and Technology Laboratory, for example, is developing a missile-stopping force field using supercapacitors: devices that store electric charge.

The idea is that, when faced with an incoming missile, supercapacitors could flood the outer shell of a vehicle with electricity to create a temporary, but powerful electromagnetic field. The blast of electromagnetism would last for less than second, but the hope is that it would be enough to repel objects. Officially, the team is calling it electric armor, which sounds less cool than a force field... but I’m not the one building it.

And they have had success with preliminary experiments, but there’s a long way to go, and the finer details of how it works are still a little fuzzy. Still, that’s more than we have for blocking radiation like laser beams. In 2014, a few undergraduate physics students did show it was theoretically possible, and they published their findings in the student-run, but still peer-reviewed, Journal of Special Physics Topics.

They suggested building a shield out of plasma, which is the fourth state of matter, and it acts kind of like a super hot, electrically charged gas. And using it to build a force field is a pretty good idea. Enough so, that big defense companies are already looking into it.

We actually see plasma block radiation all the time in space. A layer of the Earth’s atmosphere called the ionosphere is full of the stuff, and it blocks low-frequency radiation like radio waves. So if you made a really dense layer of plasma, you could potentially block higher-frequency radiation, like weaponized visible or ultraviolet light.

And since plasma carries an electric charge, it can be manipulated with magnets, so you could use a bunch of those to shape your field. The problem is, if your plasma force field is blocking lasers, it’s also blocking all other visible light. So, sure, you might be protected from the enemy’s spaceship, but you’d also be blind.

To really build a force field that would make Captain Kirk proud, we’d need to develop technology that could block both matter and radiation, all without totally disabling the crew. Right now, that seems a long way off. But maybe someday we’ll get there.

Thanks for watching this episode of SciShow, and special thanks to patron Nathan Hebert for asking the question! If you have a burning science question for us, or you want to vote on the one we answer next, you can learn more about becoming a patron over at patreon.com/scishow. [♩OUTRO].