Lightsabers are the single most iconic item from the Star Wars movies, although Darth Vader’s helmet comes in a close second.
Ever since filmgoers first saw this striking blade of light in Star Wars Episode IV: A New Hope, there has been demand for a real one. Unfortunately, science suggests lightsabers are never going to be real.
So, if you have long held a desire to own a real lightsaber, here are the reasons why that’s never going to happen… and believe us, we’re as disappointed as anyone. The problem is we cannot argue against science!
Fantasy from Reality
To give an elaborate disclaimer: Yes, Star Wars is just as much fantasy as it is science fiction, as this infographic comparing it to Star Trek shows; and if one were to begin counting the impossible or highly-improbable technologies in the series, the list would go on for quite some time.
According to George Lucas himself, the concept that became the lightsaber had its roots in the same swashbuckling adventure films and novels that informed most of the writing and art design. The peacekeepers of the galaxy needed something more noble and memorable than the blasters wielded by rougher characters like Han Solo. From that came the “elegant weapon for a more civilized age”.
A lightsaber is a fantastical object; but, as with lots of things from classic science-fiction and fantasy films, many fans want to own one of their own, and Star Wars fans can be very obsessive. Unfortunately, there are a number of scientific problems with the lightsaber that make it physically impossible, at least in the form we recognize.
Reason #1: The Science of Light
Let’s begin with the lightsaber as it is seen and described in the Star Wars films themselves. It appears to be a beam of light, generally around four feet in length.
We first see a lightsaber when Obi-Wan Kenobi hands one to Luke Skywalker, who proceeds to rather recklessly activate it and swing it around. They can be wielded in the same manner as our Earthly swords, and have the ability to slice through anything and deflect blaster bolts.
The first problem with such a blade is that light has no mass. There is no way for light to have the properties such a sword would require. Light isn’t hard enough to repel even another light, let alone long-range projectiles.
Researchers from MIT and Harvard found a way to bond photons together in a way that allowed them to behave as though they had mass. They said comparing this new discovery to lightsabers was “not an in-apt analogy.”
Don’t let their puckish language fool you. The newly-bound photons do interact with each other in a way that has never been seen, but they aren’t doing the noisy clash that lightsabers do when they are slammed together.
The second problem with having a blade of light: There is no way to stop a shaft of light at a particular length without some kind of a cap. Even if we were to assume that the light in a lightsaber is harmful, the saber would be robbed of stabbing capacity if it had a cap.
Reason #2: Impossible Combat
Lightsabers in Star Wars are treated as the be-all and end-all of weapons, capable of slicing through just about anything and deflecting blaster bolts. In this scenario the only effective defense against a lightsaber is another lightsaber.
We’re used to seeing “hard light” in video games such as Portal, but there’s really no basis in reality for that. So in the real world, a blade of light could easily be deflected by any reflective surface you had to hand. A lightsaber’s heat might be the source of its ability to slice through almost anything, but heat would not explain how it can be used to fence.
Lightsabers are wielded as if they have the same weight as Earthly swords. In the Original Trilogy, they are held with two hands and treated as if they weigh about the same as a longsword. In the Prequel Trilogy, we see them held one-handed and the experienced Jedi obviously have sophisticated fencing forms. Here’s a handy timeline if you’re having trouble keeping all of these trilogies straight.
But having a blade made of light would be to have a “blade” with no mass. There is no reason for the Jedi to wield the blades as someone would a real sword.
Reason #3: Plasma Is Hot
The films are a bit scant on information about how the lightsabers work, but the non-canonical “Expanded Universe” has quite a bit to say on the subject. According to several novels and comics, lightsabers are supposed to be plasma, refracted through special crystals.
The main ingredient in the construction of a lightsaber, coming as a surprise to no one, is The Force. Lightsabers are powered by plasma units, which cause the plasma “light” to be bent through the crystal, which is supposedly how the blades can be different lengths and colors. The Force is supposed to be what makes all of this work.
Leaving aside the space magic, there’s a big problem with that: Plasma is hot. Even “cold” plasma is too hot for the human hand to hold.
I guess we’re meant to assume that’s why the lightsaber is able to cut through just about anything, though it doesn’t explain why it has the ability to deflect blaster bolts. But unless something in a galaxy far, far away has given humanoids the ability to withstand temperatures that hit four digits Fahrenheit, it would not be physically possible to wield a plasma sword.
Reason #4: Inadequate Power
No matter what material the blade is actually made from, it would have to have a power source. This would add a lot more bulk to the sleek blade than you might think.
Let us assume that the lightsaber is somehow a functioning blade of plasma or “hard light” and is hot enough to cut through almost any substance. Powering something like that is not the work of standard batteries or gunpowder. You would probably need a separate sustained power source, which you would have to carry about your person. Something tells me that would cut down on your maneuverability.
There was a military weapon in development a few years ago that was called a “real-life lightsaber.” It was a Metal Vapor Torch, a small metal tube which released a plume of super-heated plasma that lasted for all of a few seconds and didn’t behave in any way like the elegant rapier of the films.
The reason it burned out so fast was because the amount of chemical fuel contained in the handle was only enough to power it for so long. A lightsaber would need to have an astronomical amount of power in order for it to have a stable blade for any length of time.
By the way, the only way for a lightsaber to make the signature “WWWWVV” sound would be for the power source itself to make noise. There is no reason for a beam of light or plasma to emit such a sound. But if you want to get your Windows computer to make that sound, check out our guide here.
Tell Us What You Think!
No one could be more disappointed about the impossibility of lightsabers than us geeks here at MakeUseOf. But it’s our duty to pass on the news that they’re never going to be a thing, at least not in our lifetimes.
Do you know of any similar technology that actually is possible? Do you know some way that lightsabers might be proven plausible in the future? Please let us know in the comments section below! Or just use the opportunity to talk to your fellow nerds about Star Wars.
Image Credits: lightsaber via Shutterstock