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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."
this is bullshit
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.
Forget that, I want a Wookie... Most of the fights you get into are close combat and wookies rule in that range.
Anyway, you speak of the wrong fictional universe, I speak for all Anonymous Cowards when I say that the Star Trek universe is far more interesting... Who wants to deal with the Empire (aka your average over-bloated government) when you could be like beam me up Scottie and shit like that in a commie world of tomorrow, with replicators and off world exploration for fun... I mean, which one is more realistic given our trajectory if we ever get past the lame phase of 3D printers?
AC Ruler #2
Journalists have long imagined themselves piloting X-wing fighters to free the Universe of the Evil Empire. Today, journalists have collectively decided to just fucking give up altogether. Journalists have agreed to basically denounce, forsake, and abandon every last thin thread of reality that they may or may not have been holding onto in order to retain some sort of reason, professionalism, or sanity.
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".
Correct me if I'm wrong, but I didn't think X-Wings had individual deflector shields, just the bigger ships. Definitely this is more of a Star Trek thing.
JJ prolly paid them to do the research as publicity for the new movie :-)
in order to retain some sort of reason, professionalism, or sanity.
They aren't trying as hard as you think they are.
The shield should be able to pulse on and off to allow sensors/eyes to see what's coming and turn on before predicted contact.
You wouldn't know it from how often ships would suffer a direct hit. I think Star Trek: The Next Generation was the first time a deflector shield was seen to actually be doing anything.
Switch all power to front deflector screens...
R2-D2 says "Star Wars Prequels". Not really applicable.
I look forward to angling them while you make the calculations for the jump to light speed.
Posting to undo weird mismoderation.
Ah, yes. The Ionisphere. Been using some of the layers for decades. Also, you might want to check out what Maximum Useable Frequency or MUF means.
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.
Have been talking about this for years, I understand they're working with Howard on a prototype but it's a secret so don't tell anyone.
So the Disney hype has already started, uh?
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?
Why not just use them in a proximity configuration? That would solve the "can't see shit" situation and reduce the power to run them to a minimum.
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
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)
Pnp game that had flickering shields if I'm not mistaken.
For EM radiation you basically have 3 methods:
I think a combination of the first two could be feasible, but effective energy shields alone probably will remain science fiction for the next few decades..
Then again if you think about the difficulty of creating efficient weaponized lasers, you probably won't have to worry about that anyway.
For any long distance space trip, some sort of shield like this will be necessary for larger spaceships just to protect them from dust that is flying through space at 40,000 km/h. The kind of stuff that embeds itself into the windows and tiles of the space station and space shuttle.
And they're just the little things.
Sure, space is really empty and the chances are low that you'll get hit by something but you wouldn't want to meet Murphy when you're in orbit around Titan!
Photons don't interact with each other. So no amount of magnetic field will repel a later or heat from the sun. Also not that some magnetars have magnetic fields so strong that they have energy mass equivalent density of lead.
If information wants to be free, why does my internet connection cost so much?
later should be laser.
If information wants to be free, why does my internet connection cost so much?
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.'"
It would also solve the issue of being unable to see out of the cockpit.
If you radically diffuse incoming light, that would also radically diffuse other incoming light as well somewhat like trying to see through a thick cloud. This still leaves you effectively blind unless your shield has a known transfer function that can be reversed by a camera and signal processing... but then your opponent may be able to deduct your shield's transfer function and re-focus their energy beams accordingly.
Another problem is what happens to your plasma shield when it gets hit by a high-power laser or other energy beam: unless your plasma shield is at temperatures and pressures approaching those required for nuclear fusion (what happens if external energy causes the shield's plasma to actually reach critical? I imagine it would cause some severe local disruption), a powerful enough laser would be able to locally super-heat the plasma (thin it and knock some material out of the field) and punch through it faster than flow rate can cool the hot-spot down - if you can afford pumping gigawatts into your shields and other systems, your opponents probably have the technology to pump gigawatts in their lasers.
Plasma shields sound nice in theory but in practice, they might not be practical much beyond protection from space junk and relatively crude/low-energy weapons.
Just modify the phase variance, man!
Star Trek used a lot of magic wands during its various series and movies, it's more of a Science Fantasy than Science Fiction. And some of us probably spent too much time thinking about logical consistencies, unless they're writers themselves.
Assuming that there is some magical energy source that can provide enough power and that Star Trek technology works like described in the TV series and movies:
Getting the shield frequency (gap) would be technically valid, against EM radiation weapons with a very narrow spectrum of frequencies, like lasers. In that case you could 'rotate the frequency' forcing your enemy to find the algorithm used for the rotation, if they wanted to continue exploiting your frequency gap.
However besides of Photon Torpedos, EM radiation weapons aren't that common the Star Trek universe. Phasers are particle beams, they fire "nadion particles" or are classified as plasma weapons. Disruptors use sound vibrations, plasma, particles like Nadions, antiprotons, hadrons and generally 'ions'. An energy shield would certainly work against these weapons. The only problem would be that you can't fire with these weapons, unless you take the shields down. Here you could disable the shields at a set frequency for a set pulse width and use this window to fire your weapons.
And after deflecting all Death Star's arsenal a taliban with an AK47 shots down assault team
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 ?
Of course he has a family tree, most of his closest relatives still live in theirs...
I need a wheelchair van for my son. Help me get the word out. https://www.gofundme.com/wheelchair-van-for-jj
One more thought before I go off to sleep ...
The spacecraft is the source of the magnetic field so that means the field lines have to terminate on it. Which means hot plasma is continuously blasting into you.
I always sort of thought that practical shields would work by using plasma to polarize incoming crap and then repelling it with the same containment that was used to make the shield in the first place. Stopping lasers always seemed like the very hardest part, again assuming a ridiculous source of energy.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
"Would somebody else like to estimate how much power you need to dump into the plasma ?"
Is... is it over 9000?
shields, such as those seen protecting spaceships in the Star Wars film series
won't be able to see a thing outside of your starfighter.
These two statements are incompatible.
Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
Angle the deflector shields while I make the calculations for the jump to hyperspace!
This isn't a troll, you ignorant savages. It's genius. Please thiink before allowing a hook to snag your mouth.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Magnetic fields don't have a frequency.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
No, but they can be made to change direction frequently, as the core in any transformer may demonstrate... Not sure entirely what tempoaralbeing was driving at though...
I have determined that my sig is indeterminate.
Star Wars didn't even remotely do this first... in fact, it wasn't even the first in major media, seeing as how this was the whole point of the "deflector dish" in Star Trek.
Also, they've "proven" or "demonstrated" precisely nothing, as they have tested - and derived results from - precisely nothing.
Finally, the feasibility of this was demonstrated long ago by an "odd" occurrence in a 3M plant making polypropylene film, not to mention the high-strength electro-magnetic fields (or "bottles") currently in use in experimental fusion reactors.
Just because I noticed that birds and other creatures can fly and write about it in a paper, does not mean that constitutes demonstration or proof of an assertion that human-powered flight is feasible, nor does it demonstrate the actual principle in any useful way.
"Inveniemus Viam Aut Faciemus" 'We will find a way... Or we will make one!' --Hannibal of Carthage
I know you don't do anything so twentietch-century as "reading novels", but certainly Doc Smith had force fields in the Skylark of Space, published 1928.
mark
Magnetic fields don't have a frequency.
No but Electro-Magnetic fields do, and they are just as useful as non-elctro-magnetic fields for this topic.
Truth is like the sun. You can shut it out for a time, but it ain't goin' away. - Elvis Presley (source: imdb.com)
Electro-Magnetic fields have no frequncy either.
The only thing with a frequency is the switch that activates the field and deactivates it, or reverses it if necessary/wanted. You kniw every DC current motor has a static same polarity _electro magnetic_ field (in addition to the fields of its permanent magnets).
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Yes, it works for particles, when you have sufficient energy. Technically a plasma can ionize it, and then deflect/repel it along an magnetic field, much like a particle accelerator does. Yet the same can be accomplished by EM radiation alone (ionizing radiation), which could/would subsequently create said plasma. Although I'm not sure what you could to against subatomic particles that have no charge, like neutrons.
The difficulty would not only be in stopping lasers, it's stopping any kinds of EM radiation.
For example they use their main deflector shield to protect the ship from particles at superluminal velocities, implying that these particles can penetrate the warp bubble, that bends space, around the ship.
But how does it protect them from EM radiation? Can EM radiation penetrate the warp bubble? From the series we know that you can see something from the inside of the ship, implying that EM radiation is well able to penetrate the bubble and reach the ship.
As we know from wave phenomenons like the Doppler effect, every form of EM radiation in line of the travel direction would become hard radiation (gamma rays) at high speeds, being able to penetrate thick layers of mass. Even impulse speeds could reach 4/5 c, according to VOY.So what do you do against incoming light with your shields? Remember that you can't adapt your shield to the incoming frequency before it even hits you.
Certainly with an incredible source of energy such shields might be possible, without any frequency gap, after all they couldn't use weapons and transporters during warp. But it all becomes fantastic and magical and less scientific at this point. With such kinds of energy you probably could use 'artificial wormholes' for travel.
Huh??? So visible light of various colors, radio, X-rays, infrared, microwaves, gamma rays, ultraviolet light: these are not electromagnetic fields of varying frequencies (yes, and photons at the same time)? All of physics since Maxwell has been a hoax?
No they are not electromagnetic fields. They are electromagnetic _waves_ or photons, however you look at them. In fact the term electromagnetic field is not really used, as the field looks the same like from a permanent magnet, you can not distinguish a magnetic field generated by electricity from one generated by a permanent magnet.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
http://www.physics.buffalo.edu...
Your point exactly?
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
How about dangling a miniature black hole from a stick in front of your ship? Light can't escape it!! (disclaimer: Don't let the rope break while flying)
Star Trek used a lot of magic wands during its various series and movies, it's more of a Science Fantasy than Science Fiction. And some of us probably spent too much time thinking about logical consistencies, unless they're writers themselves. ...
We live some of the science fiction "magic wands" that I read about as a boy.
They had electric cars back in the 1800's, but the power source was always the problem. The battery pack in a Tesla is pure science fiction to me!
I actually read about pocket phones with world-wide connection, in a science fiction story once. And the kids at school scoffed at the idea!
And, the rate of advance is accellerating.
It could easily be a random frequency, as long as your random number generator for the shields and for the transporters/weapons use the same seed. It's no different to how 2-factor authentication works.
Yes, the rate of advance is accelerating, fusion is only 40 years away, like it was 40 years ago. Although, this problem could be tackled.
Here we are talking about an antimatter reactor, in an universe where antimatter has to be 'created' at extremely high energy expenses and has to be contained in strong magnetic fields, which require high electrical currents, since there is no 'material' container for antimatter other than antimatter. A reactor that is so powerful that its energy can bend space itself, with the virtual mass of an entire star. A reactor that is very hard to control, therefore they had to invent "Dilithium", an element with magical properties, while being somewhat impervious to antimatter itself.
These things are preposterous, while other stuff from Star Trek is not. You might enjoy this one.