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  • 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 well 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 youve ever held a laser pointer, you know it doesn’t look anything like a

  • lightsaber for two big reasonsone, 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 lightsaberplasma 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 celsiusthat 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 roomthat 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, were 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.

  • For more episodes of How Close Are We, check out this playlist right here.

  • Don't forget to subscribe, and come back to Seeker for more episodes. Thanks for watching.

If there’s something most of us can agree on, it’s that lightsabers are awesome.

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