If there’s something most of us can agree on, it’s that lightsabers are awesome.
But this is probably the closest I'll get to holding a real one... or is it?
Now, I don’t actually mean mining kyber crystals or injecting our bloodstreams with
midi-chlorians (because everyone knows midi-cholorians are a cop out) — but instead using real
technology we have today to create something that looks, acts, and feels like the most
famous movie weapon ever.
So, how close are we to creating a lightsaber?
Now, we realize there are no actual scientific endeavors focused on specifically creating
a lightsaber at this point in time.
Sadly.
But if we were going to build our own, the first thing we need to do is look at how the
lightsaber works in the films.
If you're trapped in a cell, you might be able to use your lightsaber to cut through
the walls to be able to get your way out.
If somebody is giving you trouble in a cantina, you can chop off their arm and let them know
that you mean business.
So our lightsaber needs to be a handheld device hot enough to slice through what looks like
steel or cut off a limb.
What else?
Lightsabers are powered by a Diatium power cell.
It's essentially the battery for the lightsaber.
The beam of a lightsaber is contained by the Force powers of the user being channeled through
the kyber crystals.
Definitely don’t have any of those, so we’ll need to find an alternate power source.
Probably the characteristics of a lightsaber that make it the most dramatic and exciting
to watch are one, the glowing beam, but two, the sounds that it makes as you swing it back
and forth.That is very iconic.
Or the crashing sound of two beams coming together.
Those are some of the most iconic aspects of a lightsaber.
Ok, so in total, there are five key functions our lightsaber has to fulfill.
A natural starting place for using real life technology might be with light itself, given
the name.
Even George Lucas has previously, and confusingly, referred to the lightsaber as a laser sword.
And although it’s true that lasers can be powerful enough to cut through metal or cauterize
a wound, like current gamma knife technology we use in hospitals, they do present some
other challenges in terms of our five criteria.
So a laser lightsaber essentially is a very high-powered flashlight or a very high-powered
laser pointer.
Your standard laser pointers obviously are not going to be able to cut through metal
or anything like that.
That would be quite dangerous for all your screens and PowerPoint slides.
But if you’ve ever held a laser pointer, you know it doesn’t look anything like a
lightsaber for two big reasons — one, you can’t really see the beam from the side.
And two, the beams go on infinitely, rather than the roughly 1 meter long lightsaber.
If you want to contain the beam in a finite length, the best or easiest way to do that
with light would be to just have a mirror that can retract or be extended from the hilt
of the lightsaber and then that is able to reflect the light back and forth to create
a contained beam of light.
And it's just not going to have the look of a lightsaber.
It's going to have the look of a flashlight with a mirror on the end, even if that flashlight
is really powerful.
Also, if you were to have a lightsaber battle using this method, it would be the metal contraptions
holding your mirrors clunking into each other rather than the actual beams of light, because
the beams of light, spoiler alert, would not actually collide with one another.
One light beam will just pass through another light beam.
But what if that could be changed?
Some researchers at Harvard and MIT found that it would be possible to have photons
work together as they move through ultra-cold rubidium atoms and behave much like a molecule
in the traditional sense.
This study was able to show that they could do this for two, three photons, but in principle
if we could do this for millions upon billions of photons we could create a unified beam
of light that would be very much like a lightsaber.
Photonic molecules are very difficult to make.
They can only be generated in very precise experimental conditions.
Ah, I thought there might be a catch.
Turning light into molecules really just opens up a whole new can of space slugs, since it
would need to happen in a supercooled vacuum and a beam wouldn’t actually cut through
anything.
It again kind of takes away from the excitement and the awesomeness of a lightsaber.
I think the best method for generating a lightsaber in the real world would be to create a highly
contained plasma.
A plasma is one of the four states of nature.
You know about solid, liquid, and gas.
Plasma is, perhaps, like more gas than gas.
What it is, is when you heat up gas so much that you're actually breaking apart the atoms
so that the electrons and the center of the atoms are no longer connected together, and
they kind of move around next to one another.
If you want to see a plasma, go outside and don't look directly at the sun, but know that
if you were to look at the sun, that is a big ball of plasma.
Plasma has a lot of uses.
They can cut through metal very impressively.
Some surgeons will use plasma scalpels.
And these plasma scalpels actually make a more precise cut than an ordinary scalpel.
Now, this is definitely starting to sound more like a lightsaber — plasma checks the
box for being hot enough, but I sense another catch.
It's incredibly difficult to hold a plasma in, and so if you don't have strong magnetic
fields, it doesn't work.
This is exactly the problem that tokamaks face, the donut shaped devices that produce
controlled thermonuclear fusion power.
The trouble has to do with the fact that plasma is made up of charged particles.
Charged particles moving around make their own magnetic field.
And so, you have the magnetic field of the containment, but then you have the magnetic
field the plasma makes, and the two of them interact, and it's very hard to keep a stable
field with that very, very complicated process.
Right now if we tried to create a plasma lightsaber, it would look nothing like what we'd imagine,
and it would in fact be so large that we would be unable to hold it.
The smallest containers that can contain plasma are still large enough that a human can walk
through them.
Right.
Ok, so until we can downsize that to a handheld hilt to clip on our belt, do we have other
options in the meantime?
One possibility is that inside a lightsaber, there's like a telescopic rod.
So, like an old car antennae, the telescope would come out of a lightsaber, perhaps, made
of ceramic so it wouldn't melt and that would be the thing that would set the magnetic field
that would then control the plasma.
So, we would press the button on the hilt and the ceramic rod would begin to come out
of the handle, producing the crucial buzzing sound and the shape.
Refractory ceramics and alloys also have melting points as high as 4215 degrees celsius, so
they would be able to withstand plasma as hot as 1370 degrees celsius — that is hot
enough to melt through a steel door.
Essentially, the plasma would cut through and the rod would follow through the hole.
Ok, let’s acknowledge the bantha in the room — that kind of heat is going to be
dangerous to be around.
Essentially imagine having a cylindrical piece of the sun three inches away from your hand.
It's not going to go well for you unless you have some kind of really, really insulating
gloves, probably got to be made out of tungsten.
Done.
What about the color?
The color is very important.
Luckily, generating the different colors of a lightsaber is actually easy.
All that matters is the gas that's in the plasma.
Change the gas, get a different color.
Exactly like neon lights.
So that would mean using neon for a reddish lightsaber, krypton for a green, helium or
sodium for a yellow, and xenon or argon for a blue.
And just for you Samuel L. Jackson: mercury for purple.
Problem with that is it gives off ultraviolet light, too, which if you look at it too long
will make you blind.
Ok so maybe we skip roleplaying Mace Windu.
Got it.
What about dueling with this prototype?
If the idea of the telescoping center of the lightsaber is real, then it actually could
be those two telescoping central rods are touching one another.
But, even if somehow we were able to make magnetic fields that didn't have the telescoping
rod, what I was thinking is perhaps it would be the interaction of the magnetic field of
one lightsaber with the plasma of the other one.
After all, if the magnetic fields can contain the plasma of our saber, it will also repel
and interact with the plasma of the other saber.
So, it's a bit of a stretch, but that's maybe some way that could happen.
In order to power this lightsaber design, we’re likely going to need millions of amps
of current to generate a magnetic field powerful enough to contain this plasma.
Unless...we use antimatter?
Antimatter is something that sounds like science fiction, but it's fact.
If you mix antimatter and matter together, you get a crazy amount of energy.
How crazy is crazy?
A single gram of antimatter could produce an explosion equal to an atomic bomb.
So maybe, just maybe inside the hilt of a lightsaber, is a tiny few micrograms of antimatter,
and if there is, you got all the power you need.
In 2006, NASA actually funded research to explore the possibility of designing an antimatter-powered
spaceship.
Antimatter has the highest energy density of any known substance.
We have been able to create a nanogram of antimatter in the Large Hadron Collider, but
it wasn’t cheap.
current estimates put the cost of producing just 1 gram of antimatter at about 25 billion
US dollars.
Which is a shame, because a super teeny amount would fit perfectly in our handheld lightsaber
hilt, and wouldn’t come with the drawbacks of say, radiation from a nuclear powered lightsaber.
Ok, I think I already know the answer, but how close are we to creating a lightsaber?
Although a number of advances are required for this, individually all of these advances
are currently being researched to try to generate better batteries, to try to generate smaller
contained plasmas, and to generate high temperature superconductors.
I would probably estimate that we're still a century or two away from having a lightsaber
as we know and love them.
We can generate variations on a lightsaber today with current technology.
It's just a matter of which aspects of your childhood dreams you want to give up.
I'm not sure that we'll ever be able to make a lightsaber, and that certainly is a shame,
because it is an elegant weapon for a more civilized age.
You know?
Lightsabers might not be real, but I want them to be.
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