Replying to Physics Behind The Lightsaber

As far as the theory of a lightsaber goes, it would, in fact have to be a blade generated from some sort of plasma. The color of the plasma may even be dependent on the gases used when the blade "ignites", which is also related to the idea of the use of crystals. A widely used term to describe the sound of a lightsaber's blade igniting is "snap-hiss", which returns to the idea of a gas being the source of the blade. The crystals may theoretically be compressed compounds in a solid form, which through a simple electricity-based reaction can release a very small amount of the gas component of the compounds that they are comprised of. Barring the obvious issue of the eventual degradation of the crystals, this would provide a relatively easy to access source of the color-defining gas.

Returning to the issue of the blade being comprised of plasma, it's quite obvious that the integrity of the shape of a "blade" can only theoretically be maintained through extremely powerful and precisely calibrated magnets. The may in fact be included in the fictional component referred to as an "emitter", which is considered an essential component of the lightsaber. The best example to refer to concerning the idea of calibrated magnets and how the emitter is in fact the source of whatever energy maintains the shape of the blade would be the emitter on Obi-wan's lightsaber, which shows a distinct shape more or less akin to a satellite dish, providing the necessary points of magnetic pull against the plasma.

If one were to look at the magnetic field and how it reacts to, say, a shot from the blasters that are also rather common in the Star Wars universe, it would become apparent that both opposing forces are heated and sustained by electricity.This further reinforces the idea that blasters are also capable of firing plasma, as opposed to pure energy.

In the case of both tools, the additional problem arises with the need for a power source. A single lightning bolt, which is known to be a form of natural plasma on Earth, generates over 100 million volts of electricity from its discharge. A lightning bolt, however, lasts less than half second, longer if conditions are right. In order to sustain a constantly present blade, the energy demands would be bordering on astronomical in comparison to our current power generation capabilities. It is shown, both in movies and in the expanded universe, that lightsabers are usually ignited for several minutes to hours at a time. If not that, then they are constantly being turned on and off. This, in addition to the already existing need for a very powerful magnetic field, places a demand on the power source that would suggest that it would be necessary to have a portable-sized battery with an output equivalent to a sun.

With the composition of the blade, it's source of gas, and potential power source already covered, two problems remain which can be linked to one another.

The first being the insane amount of heat pouring off of a blade made of actual plasma. If one were to eventually overcome the need for a battery with the output of a star, a sustainable source of gas to be ionized, and a field to contain the plasma and maintain its shape, they would still have to deal with the heat of a star less than a few inches away from their hand. If another field were to be generated that could contain the inevitable radiation, this problem would be easily solved, more than likely alongside maintaining the shape of the blade. In addition to this arises the need for a metal that could survive extended exposure to the internal heat of the circuitry as well as the inevitable hole in the magnetic field that would need to be present for the blade to be ignited. This may be why it seems that the Star Wars universe also has its own series of industrial grade metals that are capable of repeatedly surviving meteor strikes, fire from weapons, and reentry into planetary atmospheres.

With these issues addressed, I would say that it is sufficient to say that we are still far, far, away from having functional lightsabers. The physics involved are known, but the technology to produce the results on a handheld scale are beyond the reach of modern technology.

star wars isnt real people lol. lightsaber technology isnt going to be around for a long long time. they have fake lightsabers, laser pen kinda stuff. this site has a lotta that kinda stuff, even ones that burn through wood. but still not real light saber.

I don't think that understanding the works of a light sabre in term of our present technology will work. The top engineers during the golden age of stream whould have had a tough time desiging a boiler to power the space shuttle. Anything we come up with for the light sabre will just be a steampunk version.

Let me suggest another angle. Since the engineers of star wars seem to have mastered gravity (artifical gravity seems to be a standard feature on all SW spacecraft) perhaps the "blade" is just a very localized, gravitationally induced disruption of space-time.

Plasma-saber theoryPhysics Behind The LightsaberReplying to iGuestUsing a magnetic field is a great idea. What is you opinion of having some sort of metal rod with pores that allow plasma to flow and act as a source for the magnetic field. That way even if the field is repelled by another saber there is still a rod you can us in defense.

You need to have a kind of confinement in order to keep the energy beam in a limited area in space.
So, if two kind of this weapons are shocking one against the other one, the confinement media will stop the opponent beam, so this kind of weapon will behave during shocks exactly like the old swords behaved some hundreds of years ago.
Of course, we still have to find how to create this confinement area and make it stable over a reasonable period of time, but his is the standard detail forgotten in each science-fiction tale.

I can't see how the physics would be possible without using some form of energy field or heat resistant reflector. Projecting a beam of light that is so intense it can cut through nearly anything would produce a constant lightwave that would simply continue travelling until it hits another surface. As far as we know, it isn't possible to control the light waves to prevent them from going any further. So really you would need an energy field projecting from the handle as well which is designed to dissapate the heat, but then the lightsaber would be useless as it would just be light trapped in a container (so to speak). I suppose you could also use a heat resistant material that travels up the inside of the beam and at the tip have some form of heat resistent reflector which bounces the light back down to the handle. This however poses the problem of, if you saber doesn't cut through an object right away you will hit the material inside the middle of the beam and maybe snap the reflector off, causing you to have more of a constant laser cannon than a sword.

<p>my idea of the lightsaber was that it was a powerful flashlight and inside the tube we all know theres a jewel in there, the jewel surronds the light and keeps it in an enclosed area, the light continues circulating the closed area and creates massive heat (hence the burns on Mace Windu when anakin chopped his arm off) </p>

This reminds of the zombie game Dead Rising 2, where you create a lightsaber by combining a jewel and torch.

Back on topic, I think the lightsaber from Star Wars was envisaged to produce actual light that has been so concentrated that it can cut through basically anything. However, the producers / storywriters probably never considered any scientific information, considering that many of the features of the lightsabers don't work in real life.

Some points / features that doesn't with scientific evidence:

- Light travels in a straight and doesn't stop until the beam of light is reflected or deflected somehow. Therefore, the fixed length feature of the lightsaber doesn't make sense scientifically.

- The light beam would have a negligible weight, so without weight, momentum in lightsaber swings would be hard to gain and fluent use of lightsaber would not achieved.

- Light beams can pass through other light beams, and would produce constructive or destructive interference. The idea of lightsabers able to block other lightsabers also doesn't make sense here.

Light Sabre PhysicsPhysics Behind The Lightsaber

The physics involved are a bit more complicated than it might seem. A laser simply won't work for this as light has a tendency to travel, barring a deflective medium, of course. The only alternative would be to project a portable singularity a set distance away from the hilt of the device that would absorb the light being emitted. Such a thing, if it could even be created, would pose a grave risk to anything in its field of effect.

A plasma field, however, could be made to fit the requirements. However, the technology as it exists, is a bit subpar for this. Generating a focused plasma field involves a tremendous expenditure of energy...Too much so to be hand portable in quite the manner as would fit a swordlike device.

Containment of the field would be the next hurdle to deal with, and a magnetic "bottle" might possibly accomplish the task. Still, a means to project that "bottle" from a remote location would be the issue, and as things are, such containment fields are more easily generated surrounding the plasma, instead of projected around it from a singular point. If this hurdle can be overcome, then one could suppose that the repulsion quality of a light saber would not be generated from the plasma itself, but rather from the "bottle" used to contain it. If the field were to be compromised in some fashion (collision with another like field of the same wavelength/ properties, for example), then the contained plasma would spill out in an uncontrolled manner, necessarily being as damaging to both wielder and target.

Curiously enough, if such a containment field could be generated that met the characteristics needed for such a device, "stabbing" a target with that field might be a trivial matter. Such a containment field, really, wouldn't need to be used to contain a plasma at all, but could be more effective as the intended weapon in it's own right.

Lastly, you have the small matter of radiative effects. Fact is, a plasma field generally emits heat. A lot of heat. In order to handle such a device, you'd need to wear asbestos garments so as not to be burned to a cinder. The light emitted would also be considerably bright, perhaps even blindingly so.

Even with all this against it, it is not impossible to consider the possibility of eventually creating a "light sabre" device using plasma and an associated  magnetic bottle field. I rather doubt, though, any of us will be around to see such a development unless we live to be rather old.

 

Although Han was able to use Luke's saber to cut the Tauntaun open to keep Luke warm. ( off topic but I always wondered what did Han do to survive the cold.) So as far as the story line goes the force is not necessary to use a light saber. In the books following ROTJ it is suggested that the sabers are powered by some type of crystal, ( consequentially the color of the crystal influences the color of the beam allowing Mace's purple or Leia's yellow sabers.) If nothing else we've found a common ground between Star wars fans and Trekkies... They both use Dilithium crystals lol. But seriously Plasma could be used and constrained using a magnetic field, the problem there is generating a typical magnetic field strong enough would add a lot of weight. I don't believe a diamagnetic field would be strong enough to constrict plasma but would be light enough to use in a hand held weapon. Maybe some kind of electromagnetic field would work. I have never heard anyone propose an electric solution, electricity like Tesla's death ray could theoretically produce a beam of pure energy. If you put any stock in Tesla's work the power is already present in the environment. However the heat produced kills this theory, it could produce a functioning saber but unless your hilt is 10 miles long you'd melt your hand,( and everything else), off

-reply by The Yetti

 

Useless without the ForcePhysics Behind The Lightsaber

As I understand it, even if you had a light saber, you can't use it without the force.  You'd be better off developing your spiritual side and leaning to commune with the midichlorians, THEN worrying about making your light sabre