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Physics Students Devise Concept For Star Wars-Style Deflector Shields
mpicpp (3454017) writes in with good news for everyone worrying about the strength of their shields. "If you have often imagined yourself piloting your X-Wing fighter on an attack run on the Death Star, you'll be reassured that University of Leicester students have demonstrated that your shields could take whatever the Imperial fleet can throw at you. The only drawback is that you won't be able to see a thing outside of your starfighter. In anticipation of Star Wars Day on 4 May, three fourth-year Physics students at the University have proven that shields, such as those seen protecting spaceships in the Star Wars film series, would not only be scientifically feasible, they have also shown that the science behind the principle is already used here on Earth."
Larry Niven will be glad to know that since he used opaque shields in "The Mote in God's Eye"
Non bene pro toto libertas venditur auro
lol, obvious troll is obvious.
"forcefields" have been a staple of pulp scifi and space opera since space opera was first born. Try something like flash gordon, AC.
Personally though, I suspect that getting a magnetic feild itself to behave as a metamaterial would be very effective in blocking coherent light beams, and probably with less power. It is important to note that magnetic field lines are themselves propagated using the same force carrier as the coherent light beam, since both are manifestations of electromagnetic energy.
You dont need to block the incoming light beam, you just need to alter the beam frequency spread so that it stops being coherent and thus disperse it before it can come into contact with the outer surface of the ship. if the shield is projected far enough out away from the craft, this would result in a radical power reduction to square centimeter of ship surface, negating the ability of the laser to in any way damage the hull of said ship. Abusing magnetic fields into acting like metamaterials has been the subject of many interesting papers already.
It would also solve the issue of being unable to see out of the cockpit.
The concept of shields was first introduced in Star Trek: Voyager.
The concept of shields was idealized permanently into mainstream SF culture in "Star Trek: The Original Series".
in order to retain some sort of reason, professionalism, or sanity.
They aren't trying as hard as you think they are.
No, "deflectors" are definately mentioned in A New Hope.
"red leader" specifically-- "bring your rear deflectors on; double front"
source:
https://www.youtube.com/watch?...
This is hardly new, scientists have been playing around with plasma windows & fields for quite some time. They're currently only a few inches in size but could be scaled up to larger dimensions, the problem is power and the pretty powerful magnetic & electrical fields needed to create them.
which one is more realistic given our trajectory if we ever get past the lame phase of 3D printers?
Evil empire? Check.
Religious fundamentalist terrorists fighting the technologically superior empire, which also happens to be controlled by someone who holds strong religious beliefs? Check.
Ridiculously expensive and often ineffective military hardware only used to fight a handful of Sand People? Check.
The future doesn't look much Star Trekky to me.
So the Disney hype has already started, uh?
Yep: any 'Star Wars' reference is guaranteed to get a few hits, and will likely be planted by a Disney marketing drone, somewhere in the evil empire (formally known as Disneyland).
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
Would be easier just to "polarize the hull plating"
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
X-Wings (all rebel fighters, actually) had deflectors. There are any number of scenes that mention them. They weren't generally intended to stand up to capital ship batteries, but rather as protection against enemy fighters.
TIE-Fighters (and bombers) did not have deflectors. They were mass-produced, cheap, crappy ships that didn't even possess hyperdrives (unlike the rebel fighters). However, your typical Star Destroyer could carry and man a *lot* of TIE fighters.
In a way, it's actually kind of funny how X-wings were so weapon-heavy when their primary opposition could probably be one-shot-killed by a single reasonably large infantry weapon. On the other hand, TIE fighters were primarily anti-starfighter, wherein "quantity has a quality all its own" makes a fair bit of sense because they could win a war of attrition with cheap fighters. The job of taking out rebel capital ships was usually left up to the (typically much larger) imperial capitals.
X-wings, Y-wings, and B-wings were designed to be effective against heavy targets (A-wings, which traded some firepower for greater agility, were the preferred rebel anti-fighter fighter), and while each one was individually superior to a TIE-fighter, the empire had a lot more TIEs than the rebellion had fighters of any kind. However, rebel fighters could effectively destroy Star Destroyers, and were also far more survivable in combat.
There's no place I could be, since I've found Serenity...
Yes, metamaterials. The problem is that the bandwidth is quite narrow as far as I know, covering a broad spectrum of frequency is far from trivial. Here the rule of thumb is that the structures in meta materials have to be smaller than the wavelength, they're supposed to affect. Photonic crystals also have to be created with a very specific bandgap. Another problem is that metamaterials are matter, a magnetic field by itself isn't matter and can only change the polarity of electromagnetic waves, which won't do much. Now you could say that you manipulate the matter around with with said magnetic field, make the former "energy field" into an "energy-matter-field", which raises a problem in space, since space isn't known for its high density of matter. Then you'd have to emit matter and keep it in place around your ship. Thank god Star Trek also invented replicators, eh?
Which is why frequency matters (no pun intended).
The basics of it is that all matter can be repelled using the correct frequency. So by varying the frequency of the magnetic field you can repel various kinds of matter; which of course means that the magnetic shields are not full proof - somethings will be able to get through them if they don't resonate significantly enough with respect to any of the frequencies employed.
Truth is like the sun. You can shut it out for a time, but it ain't goin' away. - Elvis Presley (source: imdb.com)
Considering Obi Wan gives props to the precision of Stormtrooper marksmanship, one has to assume they actually had damn good aim.
Not quite: plasma windows exist.
And any protection against lasers is going to be opaque or reflective at the laser frequency, or it isn't going to be very effective.
If you want it to be effective against all frequencies of a Free Electron Laser you need it to be completely opaque or reflective, so you wouldn't be able to see out of it.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
Wait, they couldn't hit the ewoks? I can never tell because of all the fast forwarding I'm doing.
I've been looking into making one myself as a hobby project, to go with my can-crusher/disc-launcher. So far it's gotten as far as generating a very strong magnetic field (Solonoid, and it draws 500A at 12V - I'm powering it off an ultracap bank). Progress stopped there, because the next part of my design requires a supply of at least fifty kilovolts, DC, and that doesn't rectify easily. It'd need specialised, very expensive parts.
The end goal is to flick marbles at it and watch them bounce off.
Lasers? What lasers?
Those things on SW aren't lasers. One, they travel too slow (you can actually see the gaps in the pulses) and, following on from that, you can see them when they're not travelling right towards your remaining eye.
Also, lasers don't go "pyew pyew!" and even if they did you wouldn't be able to hear them through a vacuum.
Finally, parsecs.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
This is extremely difficult to achieve and would require a lot of energy to work as an effective, impenetrable "shield", which would act much like extremely strong white noise generator.
This would explain why getting the enemy's shield frequency is technically valid. (The shield frequency had to be nonrandom, because otherwise you couldn't fire or transport through it.) A lot of problems go away if you wave some magical energy source wand over them.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I can't even think of a movie (other than Gravity) that did this correctly.
'2001' did. When HAL went and cut Frank Poole's airline during his EVA, his death was shown completely silently and I think it had a far greater impact as a result.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
The paper is a one pager of introductory plasma physics. It isn't a serious calculation and it wasn't meant to be. Anyway ...
Their model is as follows. A plasma will reflect all electromagnetic radiation below a certain frequency, determined by its density. The plasma exerts a pressure like a gas and they then assume confinement of the plasma with a magnetic field, balancing the plasma pressure with the 'pressure' that a magnetic field exerts on charged particles. They then say that we can make magnetic fields in the range up to 100 T and working back, estimate the plasma frequency, which turns out to be in the UV. So great, you can deflect lasers into the UV with a modest confining field.
You need to look at some of the other numbers though. .... The other problem is that at such a high density, the collision frequency is very high so that a magnetic field is not very effective at producing confinement. Probably useless in fact.
First, what sort of plasma density do you need to reflect UV ? The answer is something like 10^28 per cubic m. This is enormous - fusion plasmas are about a million times less dense). It's getting close to solid state density eg if a solid has atoms 0.2 nm apart this is 10^29 atoms per cubic m. That is not going to be easy
The other thing to look at is the required plasma temperature. They assume a temperature of 1000 K, Unfortunately, the density of a plasma at 1000 K at thermal equilibrium is extremely low unless the background pressure is huge. So it has to be a lot hotter, in particular, comparable with the ionization energy which is roughly 100 000 K. And really, we need a fully ionized plasma because the magnetic field is not going to confine the neutral gas that we are using to make the plasma so that means we need a 100 000 K plasma. This means that the required magnetic field goes up by a factor of 10.
Would somebody else like to estimate how much power you need to dump into the plasma ?
Nerd hat on...
Photon torpedoes are from Star Trek, they are matter/anti-matter missile weapons fired from the ship in a torpedo casing. They have guidance and a warp sustainer engine so if fired at warp they can maintain warp speed for a short period of time. (Phasers are directed energy weapons and thus can't be used at warp)
Proton torpedoes are from Star Wars, they also are a cased missile weapon, much smaller than photon torpedoes, the X-Wing carries 6 of them, 3 per launcher. They are anti-capital ship weapons, unable to target most fighters, they are designed to penetrate thick durasteel hulls and explode inside the ship.
As a dramatic/horror type scene, yes.. but for an action based space opera, it just wouldn't be remotely as engaging without the pwew pwews added in. They had the exact same discussion when developing the original Star Trek series in the '60s (and probably for TNG again too), and knowing full well there is no sound in space, they nonetheless decided to dub it in anyway after doing some tests. Consider it poetic license.
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
It turns out that rectifying 50 kV is easier for a hobbyist than you may think. I was also once in a situation where I needed to do rectify high voltage. I bought a 120 kV medical X-ray machine on eBay years ago, less a power supply. The seller sent me (free!) a quad of antique KR-9 kenotrons, very large oil-cooled rectifier tubes. I was planning to use them for a bridge rectifier with the 1:800 transformer I found (though X-ray tubes can operate in self-rectifying mode, it's only active during part of the AC cycle). Unfortunately, after an argument my ex broke all but one of the kenotrons (which I'm especially bitter about now, after seeing a single one go on ebay for ~$150). But onto the solution. You can get 12-15 kV solid state rectifiers online in bulk from Chinese manufacturers. I bought 100 of them for around $40, though I don't remember if it was alibaba or another of these sites. The ones I got are good for an amp or two. Make a series and/or parallel network as needed to get to the voltage and current rating you need, making sure to add an extra 30% for peak inverse voltage because the rectifiers won't be perfectly matched, even if they're from the same batch by the manufacturer (if you're really worrying about mismatches, add a resistor divider network in parallel, connected at each node, to even out the voltage across each diode--set the resistance for about 10% idle current--and your use case must be able to take that amount of reverse leakage into account). Now the most important part--avoiding arcing. Take a PVC pipe that will fit your network, and two end caps to which you add screws as end terminals, and epoxy them in place. Connect your rectifier chain to the end-caps, stuffing it into the pipe, then fill the pipe with pure paraffin wax before sealing the second end. You could use transformer or even regular mineral oil (I'd not recommend baby oil, though), but it's likely to leak and that shit's hard to clean up--I use it for the transformer and speak from experience.
"Politicians and diapers must be changed often, and for the same reason."
Those are long-service regulars. Later on in the movie they've had to resort to conscription.
Shit, I can't believe I'm trying to make sense out of star Wars.
If you really want to make sense of the movie, just realize that the scenes where they can't hit anything is where they are actively trying to let the rebel princess escape so they can get onto a ship with a tracking beacon to lead them to the rest base which they really want. That plan couldn't work if the stormtroopers actually hit and killed everybody. Even Leia said the escape had been too easy. face it, all those stormtroopers had orders to miss.
I'll have to look into that approach. I don't know my current requirements, they would need to be determined experimentally, but my plan is to have a circular (ring) anode and a spherical cathode in the middle, with the electrons thus forced to take a spiral path - much like in a magnatron, except without the vacuum.
I did determine that it's very hard to strike an arc in a strong magnetic field.