The Science Behind the Jedi Lightsaber: How Far Are We From Making Our Own?

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With the explosive success of The Force Awakens, interest in all things Jedi has come to fever pitch. And perhaps no item is more evocative of the film’s fascinating world as the Jedi lightsaber. It’s no surprise that many of us wonder: how far are we from holding one of our own?

According to this animated infographic, we’re already 75% there – but that last 25% still seems elusive indeed. Let’s explore just how close we are to protecting our galaxy with this ‘elegant weapon for a more civilised age’.

Is a Lightsaber Exactly?
Yes, most of us can probably bring the lightsaber-wielding Jedi to the mind’s eye without too much difficulty. But if we’re going to delve deeper into reproducing them in the real world, we need to understand exactly what the films suggest they’re made of and what they can do.

Firstly, it’s easy to see that they’re incredibly powerful. They easily slice through solid chunks of metal, cut through flesh, yet the hilt’s temperature is controlled so as not to harm the user. The laser itself can also be ‘turned off’ at the press of a button, allowing the Jedi to put away their weapon in a holster.

Overall, it’s an incredibly flexible weapon that combined with a Jedi’s power is a force (no pun intended!) to be reckoned with. Science, however, is proving to be a worthy adversary that’s stopping Lucas myth from becoming reality.

Stopping the Beam
The lightsaber seems to use lasers of some sort – however, those in our world are invisible until their end point and also don’t have a fixed length. We’re nowhere near developing the technology to stop the laser beam in its tracks. Light needs to hit something solid to stop, or it needs to be refracted through the use of a mirror.

The conclusion? It doesn’t seem possible that we could ever use lasers in their current form to build something similar. The beam of laser light would simply continue exponentially and would not be shown until reaching its natural end – just think of a classic laser pointer as an example.

Finding a Power Source
While we currently have plenty of options to power up an item that emits light or plasma of such magnitude, there’s one ‘minor’ problem. Contrary to what the lightsaber suggests (such as a small battery pack), reality calls for something a little more expansive.

What we’re left with is a weapon that can only last for just a few seconds or a bulky and heavy item that would not be possible to use as anything like a sword. The familiar noise of the lightsaber would also come from the power source, as plasma or light do not naturally emit such a sound.

Light Has No Mass
Another issue that we have is that light has no mass. The lightsaber is more powerful than any sword or axe, yet light has no properties that would allow such behaviour.

Consider the fact that light does not even have the capability to repel other light, yet in Return of the Jedi we clearly see Luke defeating his enemies by repelling blaster shots. Unfortunately, our own laws of physics would now allow this. You can imagine how feeble a lightsaber duel would look with the two weapons simply bypassing each other!

The films themselves are also not exactly consistent. In the original trilogies the weight of the weapon suggests something similar to the longsword (hence the slow and pensive fighting style), but the prequels have ‘upgraded’ the weapons to be lightweight fencing instruments. Regardless of which it actually is, light itself would weigh less than both.

What About Plasma?
GE Engineer Matt Gluesenkamp has stated that the closest real-world example of what the lightsaber consists of is plasma generated electrically. The problem with using plasma in this manner is that the battery power that would be required to create this amount of electricity would render the weapon unusable.

Another problem is the sheer heat of plasma. The suggested temperature of the lightsaber would hit four figures Fahrenheit, yet all our heroes need is a handy hilt that is seemingly capable to withstand such temperatures.

Unfortunately, we currently have no such material that would be able to do something similar. Not only that, plasma emits heat as well, which would mean that anything even a few inches from the lightsaber would be charred beyond recognition!

New Findings
While Time Magazine sensationally reported that the fabled Jedi weapon is finally a reality, the headline is unfortunately closer to click-bait than anything else. Nevertheless, the findings by scientists at Harvard and MIT are promising indeed.

Teams of physicists have worked together to bind photons that can be said to behave in a similar manner to what we’d expect from the Skywalker weapon of choice. As a byproduct of other experiments, scientists have observed that photons fired through rubidium atoms behaved in a unique manner.

Opposite to massless particles that don’t interact with other molecules, in this case they would form together and move in a uniform manner. This effect is essentially what the lightsaber suggests it’s doing, which perhaps forms a basis for future developments.

However, what we currently have is still way off a working model. While the particles do indeed interact in an entirely novel way, it’s still a simple interaction. There’s plenty of work to be done before we have our own versions of Luke and Obi-Wan protecting law and order. Considering just how impossible this particular behaviour seemed just a few years ago, Star Wars fans are allowed to remain hopeful.

We’re not there yet, but technological advancements of recent years make it feel as if the lightsaber is scintillatingly close. Nevertheless, the presented obstacles are perhaps yet still a bridge too far and it may be several generations before we’re capable of reproducing what they managed a long time ago in a galaxy far, far away.