Opinions/problems on a "force field"

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Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Thu May 22, 2008 1:33 am UTC

I'm 16 so I need help from all you clever internet people with this please. If you have a ship In space, since space is simple, and you envelop it with a big, very thin, superconducting mesh like so
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Now run a huge amount of current through that. As soon as anything touches that (hyper space bullets, meteoroids, or what have you) It pretty much explodes ( remember, a LOT of current) I have no idea how to determine how much energy that would take (would be cool to know, hint hint), and the newly vaporized particles would not (?) cool down since there is nothing to cool them, but they would have a similar effect to sparks (no energy actually imparted), and the kinetic energy will be spread out hugely.

Lasers and stuff in space would be silly when you have something like this :http://gizmodo.com/351467/navy-rail-gun-test-destroys-everything-it-touches-at-5640-mph that won't explode in a vaccum. theoretically would plasma or lasers, having low kinetic energy, be affected by a flux exclusion if the mesh were rigid?

Basically... would this be effective? would superconductivity be possible to maintain in sunlight/solar wind? or would we need a super high temperature superconductor (curses)?

It seems like this is also sort of a reactive armor to defend against rpgs on tanks by vaporizing the copper. not sure how that would work.

edit: pic messed up and a big very tiny mesh makes no sense
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Re: Opinions/problems on a "force field"

Postby Kaiyas » Thu May 22, 2008 1:48 am UTC

I don't think simply vaporizing the projectile's going to protect the field itself. Hence, a bajillion dollars down the drain everytime it gets hit.

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Re: Opinions/problems on a "force field"

Postby Luthen » Thu May 22, 2008 2:03 am UTC

Have you asked the people in the Science forum? This is right up their alley.

Not really a force field is it? Sounds like an extreme electric fence.
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Re: Opinions/problems on a "force field"

Postby gmalivuk » Thu May 22, 2008 3:39 am UTC

Luthen wrote:Have you asked the people in the Science forum? This is right up their alley.

Agreed, which is why I've moved it into here.
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Re: Opinions/problems on a "force field"

Postby Antimony-120 » Thu May 22, 2008 3:58 am UTC

you might be better off to actually charge the entire thing, allowing this high charge to result in a high voltage (compared to the neutral space debris) and use that to create large arcs to vaporise things. Not that it's very cost effective given the permittivity of free space, but that way things wouldn't have to make contact before exploding, thus you wouldn't have to repair the mesh every five seconds. Of course this raises the question of where you put your opposite charge (whatever you stripped/added onto the mesh has to goto/come from somewhere) and the massive forces that would be involved with such a charge separation.
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Re: Opinions/problems on a "force field"

Postby evilbeanfiend » Thu May 22, 2008 7:13 am UTC

as well as a high Tc superconductor its going to have to be a very high Ic superconductor if you are wanting to shove lots of current through it. if you put to much current in then it will drop out of the superconducting phase. you will also need to be careful about moving in mag fields for a similar reason.
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Re: Opinions/problems on a "force field"

Postby Ironmon1 » Thu May 22, 2008 7:43 am UTC

*puts on physicist hat*
In short, no.
First, this would be great for all things charged: a nice magnetic field to deflect particles; the problem is with the uncharged particles- your mesh will do nothing to them.
Explode? Why? They don't have "ground", an place for the current to go. You would get a small amount of charge from the (minuscule) capacitance of the particle, but not enough to matter. As a radiation sheild, your mesh is wonderful, even without much or any current, but as a particle sheild, it's useless.
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Re: Opinions/problems on a "force field"

Postby Turambar » Thu May 22, 2008 9:01 am UTC

This gives me an idea, though: Have a charged outer shell, preferably positively charged, since I think most of the solar wind and interstellar gas will be protons. This mesh will need to be at a large radius from the ship. Now, within the ship, one could have superconducting solenoids (preferably three, mounted at right angles to each other) which would produce a massive magnetic field that would cause any incoming charged particles to be deflected, since no matter what angle they come from, they'll be at a large angle to one of the magnetic fields.

On second thought, I'm not even sure that you would need the charged mesh around the ship, since most of the interstellar medium should be protons. In fact, if the ship is traveling forward at high velocities, one properly oriented magnetic field ought to account for all the dangerous trajectories of incoming particles. The field would simply need to be oriented at a right angle to the direction of the ship's velocity.

Naturally, this would probably use a large quantity of energy, though the fortunate thing is that a magnetic field doesn't need to be stronger because of the additional velocity of incoming particles, since magnetic force is beautifully proportional to particle velocity. It might almost be feasible.

Problems might arise if a larger portion of space dust is neutral than I thought. Actually, come to think of it, it might well be, because if interstellar dust clouds are absorptive in the Balmer lines, then they must needs have electrons. But maybe only the large clouds have those. I am under the impression that much of the interstellar medium is what was blown out there by the solar wind.

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Re: Opinions/problems on a "force field"

Postby Antimony-120 » Thu May 22, 2008 12:49 pm UTC

It's true that most of the intersteller dust is ionized, or else we wouldn't be able to see very far at all.

http://en.wikipedia.org/wiki/Reionization
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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Thu May 22, 2008 10:09 pm UTC

Hmmm, so touching a superconductor wont electrocute you? It has no resistance so why should it go through you. Had never really thought of that.

Anyway the reasoning behind it was you get a ton of cheap (heh heh) superconducting meshes, and each time they get hit they blow the particle up, and the heat causes a cascade failure as the heat spreads, resistance appears and it melts itself.

Having huge arcs to destroy space debris seems kinda silly- you would have to have somthing with a huge resistance so that the electricity would rather jump off and back by a significant distance with a significant power, just to go through a little projectile. Wouldn't that much resistance just fry itself?

Anyway, I thought of another solution, much less feasible. Instead of having a mesh, you have single, superconducting wires going parallel to each other. When something hits one of them, it interrupts the circuit so the electricity is forced through the object, vaporizing it.

This is pretty useless in terms of any application: natural debris are easy to deal with with thick armor+magnets (or just have a superconductor protected somewhere under the hull), and in terms of warfare there are 2 types of possible weapons: The railguns from before or missiles. Railguns would be unreliable for repeated damage, and missles could be easily killed by, say, an HERF gun (a la http://xkcd.com/322). Space wars don't really work.

If you made it out of metal then vented the ships atmosphere slowly enough that it formed into a sphere around the ship, and THEN turned the current on, I bet you could get something like this:
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Re: Opinions/problems on a "force field"

Postby Turambar » Fri May 23, 2008 9:06 am UTC

RAPTORATTACK!!! wrote:Anyway, I thought of another solution, much less feasible. Instead of having a mesh, you have single, superconducting wires going parallel to each other. When something hits one of them, it interrupts the circuit so the electricity is forced through the object, vaporizing it.

Interrupting the circuit wouldn't cause any frying, what you would need is for the incoming debris to be the closing switch in a circuit. Maybe if there were a mesh of many parallel superconducting wires (plenty of things are superconductors in the temperatures you get in vacuum), but all of the wires have a small gap in them at some point. These gaps would need to be staggered so that wherever the debris hit, it would close a circuit. Actually, I think that'd be pretty inefficient to make.

This is pretty useless in terms of any application: natural debris are easy to deal with with thick armor+magnets (or just have a superconductor protected somewhere under the hull), and in terms of warfare there are 2 types of possible weapons: The railguns from before or missiles. Railguns would be unreliable for repeated damage, and missles could be easily killed by, say, an HERF gun (a la http://xkcd.com/322). Space wars don't really work.


Well, railguns, if you used a few relatively largish ones, would probably work pretty well. You could get some fantastic velocities out of them.

Also, antimatter would be extremely useful. It would be prohibitively difficult to store it, but if there were a way to manufacture it within the weapons systems of the ship, that could prove useful. And if a missile were equipped with a Faraday cage, then it could probably withstand any EMP-style weapons thrown at it. I wouldn't necessarily rule out lasers either. The massive energy required for propulsion of a spaceship would probably be sufficient to power a laser strong enough to damage another ship, or at least to destroy its optics and sensor arrays.

In fact, if a spaceship has a very high-energy propulsion system, one of its best weapons might be the engines themselves, because they would constantly spew out particles at very high speeds. Which leads to an amusing image of space battles: Ships encounter each other and immediately turn around and go the other way as fast as they can.
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Re: Opinions/problems on a "force field"

Postby evilbeanfiend » Fri May 23, 2008 9:13 am UTC

Turambar wrote:(plenty of things are superconductors in the temperatures you get in vacuum)

a vacuum may have no heat but it also has no heat capacity and no conductivity, things don't superconduct just because you stick em in a vacuum (in fact spacecraft generally have trouble getting rid of unwanted heat as this can only be radiated away)
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Re: Opinions/problems on a "force field"

Postby Turambar » Fri May 23, 2008 9:26 am UTC

evilbeanfiend wrote:
Turambar wrote:(plenty of things are superconductors in the temperatures you get in vacuum)

a vacuum may have no heat but it also has no heat capacity and no conductivity, things don't superconduct just because you stick em in a vacuum (in fact spacecraft generally have trouble getting rid of unwanted heat as this can only be radiated away)


Yeah, but as long as we're talking about a thin-wire mesh made of metal, it will have a very high surface area to volume ratio, and so the amount of heat it loses to thermal radiation will be much greater than the amount it can insulate itself. I can't answer for the spaceship itself, but cycling the ship's air through radiating fins ought to do the problem.

Also, I suspect a large part of the heat problem for spacecraft is due to the Sun. I'll assume that most of the extremely high-velocity collisions that need to be prevented are not going to happen very close in to a star, and so there will be a lot less solar radiation heating the thing up.
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Re: Opinions/problems on a "force field"

Postby evilbeanfiend » Fri May 23, 2008 11:09 am UTC

the sun has a big effect yes but dissipating heat from energy used by the craft is also a big factor (you are looking at getting rid of multiple kW of power for a modern satellite without considering heating from the sun). internally you can use heat pipes (no air on an unmanned craft, but maybe you'd use air on a manned one) to even the heat around the craft but to actually get it off the craft you need to radiate, the trouble you get then is that good thermal radiators also work well in reverse.your craft is generally in a complex multi-body orbiting system so your radiating panels might be pointing at 4K deep space at one moment and be reasonably efficient, a 300K planet the next and do nothing, and then the sun swings into view and they are actually heating the craft. obviously its a solvable problem unless you get too close to the sun but it is quite a complex one.
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Re: Opinions/problems on a "force field"

Postby ave_matthew » Fri May 23, 2008 12:33 pm UTC

I also had the (outer charging field/inner repelling field idea), but depending on what sort of speed you were going at, wouldn't any mesh be under far too much stress (heat..) up around .2C I doubt it could survive.

Better to simply avoid using space at all via wormholes ;)

And at low speed, maybe you could have lasers/something that shot at incoming projectiles with the same idea as the missile defense grid?
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Re: Opinions/problems on a "force field"

Postby BlackSails » Fri May 23, 2008 6:23 pm UTC

Turambar wrote:
RAPTORATTACK!!! wrote:Anyway, I thought of another solution, much less feasible. Instead of having a mesh, you have single, superconducting wires going parallel to each other. When something hits one of them, it interrupts the circuit so the electricity is forced through the object, vaporizing it.

Interrupting the circuit wouldn't cause any frying, what you would need is for the incoming debris to be the closing switch in a circuit. Maybe if there were a mesh of many parallel superconducting wires (plenty of things are superconductors in the temperatures you get in vacuum), but all of the wires have a small gap in them at some point. These gaps would need to be staggered so that wherever the debris hit, it would close a circuit. Actually, I think that'd be pretty inefficient to make.


http://en.wikipedia.org/wiki/Reactive_a ... ive_armour

Have two layers of superconductors, seperated by an thin insulator.

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Re: Opinions/problems on a "force field"

Postby Turambar » Sat May 24, 2008 1:14 am UTC

BlackSails wrote:
Turambar wrote:Interrupting the circuit wouldn't cause any frying, what you would need is for the incoming debris to be the closing switch in a circuit. Maybe if there were a mesh of many parallel superconducting wires (plenty of things are superconductors in the temperatures you get in vacuum), but all of the wires have a small gap in them at some point. These gaps would need to be staggered so that wherever the debris hit, it would close a circuit. Actually, I think that'd be pretty inefficient to make.


http://en.wikipedia.org/wiki/Reactive_a ... ive_armour

Have two layers of superconductors, seperated by an thin insulator.


Hey, that's a good idea, wish I'd thought of it.

I imagine it would still result in plenty of large rips in the shield material, though... If parts of the inner and outer shell became fused together, then it would be hard to keep a potential difference between them.
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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Sat May 24, 2008 10:15 pm UTC

Turambar wrote:
BlackSails wrote:
Turambar wrote:Interrupting the circuit wouldn't cause any frying, what you would need is for the incoming debris to be the closing switch in a circuit. Maybe if there were a mesh of many parallel superconducting wires (plenty of things are superconductors in the temperatures you get in vacuum), but all of the wires have a small gap in them at some point. These gaps would need to be staggered so that wherever the debris hit, it would close a circuit. Actually, I think that'd be pretty inefficient to make.


http://en.wikipedia.org/wiki/Reactive_a ... ive_armour

Have two layers of superconductors, seperated by an thin insulator.


Hey, that's a good idea, wish I'd thought of it.

I imagine it would still result in plenty of large rips in the shield material, though... If parts of the inner and outer shell became fused together, then it would be hard to keep a potential difference between them.


At the risk of forming a giant quote chain: Let me explain more better. The parallel wires are thin enough so that upon being hit, they break, and the projectile completes the circuit, and not being a superconductor, the current breaks it. Then some automated system replaces it, so the armor can remain active, whereas in the full shell method, spraying it with bullets will either kill the shield completely or deactivate large portions, and is virtually irreplaceable under attack.

Problems- the wires could conduct between each other instead. Also, it would be difficult to maintain a cold enough temperature without wasting, say, liquid nitrogen to spray it periodically. Is not being able to cool down that big of a problem in space? Also, since potential energy isn't building up, you need a fantastic amount of energy.
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Re: Opinions/problems on a "force field"

Postby BlackSails » Sun May 25, 2008 5:55 pm UTC

RAPTORATTACK!!! wrote:
At the risk of forming a giant quote chain: Let me explain more better. The parallel wires are thin enough so that upon being hit, they break, and the projectile completes the circuit, and not being a superconductor, the current breaks it. Then some automated system replaces it, so the armor can remain active, whereas in the full shell method, spraying it with bullets will either kill the shield completely or deactivate large portions, and is virtually irreplaceable under attack.

Problems- the wires could conduct between each other instead. Also, it would be difficult to maintain a cold enough temperature without wasting, say, liquid nitrogen to spray it periodically. Is not being able to cool down that big of a problem in space? Also, since potential energy isn't building up, you need a fantastic amount of energy.


No, because the bullets are vaporized by the high currents. They dont short out the layers permanently. Once vaporized, you can just patch that section.

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Re: Opinions/problems on a "force field"

Postby troyp » Sun May 25, 2008 11:38 pm UTC

In regards to the last several posts:
Forgive my ignorance of such electrical matters, but would this work with a superconductor mesh?
With such low resistance, wouldn't almost all current go around the object, with only a tiny fraction actually passing through it?

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Re: Opinions/problems on a "force field"

Postby Turambar » Sun May 25, 2008 11:44 pm UTC

BlackSails wrote:
RAPTORATTACK!!! wrote:
At the risk of forming a giant quote chain: Let me explain more better. The parallel wires are thin enough so that upon being hit, they break, and the projectile completes the circuit, and not being a superconductor, the current breaks it. Then some automated system replaces it, so the armor can remain active, whereas in the full shell method, spraying it with bullets will either kill the shield completely or deactivate large portions, and is virtually irreplaceable under attack.

Problems- the wires could conduct between each other instead. Also, it would be difficult to maintain a cold enough temperature without wasting, say, liquid nitrogen to spray it periodically. Is not being able to cool down that big of a problem in space? Also, since potential energy isn't building up, you need a fantastic amount of energy.


No, because the bullets are vaporized by the high currents. They dont short out the layers permanently. Once vaporized, you can just patch that section.


Yeah, but the point is that in the middle of a space battle, or while in very high-speed transit, it would be difficult if not impossible to replace parts of the shield.
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Re: Opinions/problems on a "force field"

Postby Fossa » Mon May 26, 2008 12:00 am UTC

Its worth pointing out that due to the nature of super conductors a "mesh" is a laughable impossibility. Superconductors are superconductors because they have an infinitely long mean free path as electrons are "towed" in one anothers wake. They have to be moving in a perfectly straight line, though. You can only get two dimensional rings.

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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Mon May 26, 2008 1:41 am UTC

I have very little idea how they work at the molecular level, since there's only so much wikipedia can teach.

If it can only go in straight lines, then how does a ring work? :| Why wouldn't a sphere work? Geometrically it's just a bunch of circles after all. :?:

Finally, how do the valence shells and conduction shells overlap in a superconductor? or does it not matter because the electrons travel differently?

troyp wrote:In regards to the last several posts:
Forgive my ignorance of such electrical matters, but would this work with a superconductor mesh?
With such low resistance, wouldn't almost all current go around the object, with only a tiny fraction actually passing through it?


The shell isn't superconducting. The reason this is possible is because the insulator between the layers acts as a capacitor and builds up a huge amount of potential current. When something connects them, they conduct through it. Then the shell rebuilds the potential, and starts again. Of course, then you have a gaping hole and you need to recharge.

The mesh doesn't work for the reason you said, which is why is suggested the parallel wires. It also doesn't depend on potential buildup. However, It doesn't depend on potential buildup. This means you need huge amounts of current run through it continually (unless you do something mildly clever with electronics).

Plus, this way is way cooler. :mrgreen:
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Re: Opinions/problems on a "force field"

Postby Fossa » Mon May 26, 2008 2:00 am UTC

By "line" I meant "non-branching path".

Basically what happens is you have a grid like lattice of positively charged ions. As a single electron passes through this grid it draws the ions above and below the electron towards it creating a region of dense positive charge just behind the electron. This is often referred to as the electron's "wake". Behind this electron you'll have a paired electron which, even if it should interact with an atom and have its path disrupted (non-infinite mean free path) it will get pulled back to where it should have been very quickly by the wake of the electron ahead of it.

This process continues back down the line so that if any electron travelling, for all intents and purposes, "single file" through the crystalline superconductor is knocked astray its pulled back to where it should have been. It almost behaves as if no charge carrying electrons interact with the atoms of the superconductor (tiny amounts of energy are lost with each collision, but if its a single crystal (or low angle grain boundaries) this is rare). The mean free path is effectively infinite.

A neat trick with superconductive rings is that once you have a current flowing (induced by a magnetic field) you can stop the source of the current and the electrons will continue to travel in the ring for quite a while, each one drawn by the one in front of it while pulling the one behind it. Eventually the occasional collisions will stop the current as energy is expended to "pull" the electron back in line.

Edit:

A very simple diagram can be found here to help you visualize this:

http://www.nature.com/nmat/journal/v2/n ... 90_F1.html

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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Mon May 26, 2008 2:11 am UTC

Oh! Perovskites! The highly charged non oxygen atoms do that. Also the copper planes in YCBO. Clever.

That's actually really neat. Is that how they all work or just some? Do high temperature superconductors just create the positive regions more easily?

edit: I'm guessing that this means the levels overlap with the adjacent atoms once a traveling charge is induced?

How does heat fit in? Does it have that big an effect on the atoms in the superconductor? :?
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Re: Opinions/problems on a "force field"

Postby Fossa » Mon May 26, 2008 2:13 am UTC

RAPTORATTACK!!! wrote:Oh! Perovskites! The highly charged non oxygen atoms do that. Also the copper planes in YCBO. Clever.

That's actually really neat. Is that how they all work or just some? Do high temperature superconductors just create the positive regions more easily?


Thats how the high temperature ones work. Not sure about the low temp ones. A group working in my lab is actually making perovskite superconductors which is how I know this.

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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Mon May 26, 2008 2:29 am UTC

Plus there are other ones that are different. According to Wikipedia, of course.
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Re: Opinions/problems on a "force field"

Postby BlackSails » Mon May 26, 2008 1:31 pm UTC

Turambar wrote:Yeah, but the point is that in the middle of a space battle, or while in very high-speed transit, it would be difficult if not impossible to replace parts of the shield.


Thats true of all armor. Just make sure you dont get hit in the same place twice. Or layer the armor like an onion.

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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Mon May 26, 2008 9:55 pm UTC

Yeah, and the point of having a force field is that it isn't like all armor. Its nullifies all incoming projectiles and isn't destroyed. This is about as close as you can get without magic.
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Re: Opinions/problems on a "force field"

Postby evilbeanfiend » Tue May 27, 2008 8:42 am UTC

Fossa wrote:
RAPTORATTACK!!! wrote:Oh! Perovskites! The highly charged non oxygen atoms do that. Also the copper planes in YCBO. Clever.

That's actually really neat. Is that how they all work or just some? Do high temperature superconductors just create the positive regions more easily?


Thats how the high temperature ones work. Not sure about the low temp ones. A group working in my lab is actually making perovskite superconductors which is how I know this.


yes the low temp ones have paired electron's (cooper pairs) too which work in a similar way iirc (electron phonon interaction) however generally the low temp ones are more symmetric in all directions, not being confined to CO planes etc.
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Re: Opinions/problems on a "force field"

Postby daryuu » Tue May 27, 2008 9:28 am UTC

RAPTORATTACK!!! wrote:This is about as close as you can get without magic.


Back in high school one of my closer friends was constantly talking about an idea for armor wherein the exterior panels were all wormhole generators, and the wormholes (somehow) lead to the exact same space but oppositely directed. So then, if something hits the armor it literally pushes against itself until it stops (and lasers wouldn't fare any better). He touted it as the ultimate mirror armor.

I never really agreed with him that it even made any sense, and some of my other friends had a lot of fun poking holes in his defense, but if you could somehow make wormhole generating panels like that it seems like it would be a little closer to the objective here... The exceptions of course being that certain parts of the ship that need to be exposed, like the thrusters and whatever you're using to figure out your position...

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Re: Opinions/problems on a "force field"

Postby Beacons! » Thu May 29, 2008 3:27 pm UTC

Have you read Michio Kaku's latest book? That has a really good suggestion on how to create a useful forcefield. I don't want to type it out here because of copyright etc. But its pretty darn good.

EDIT: More detail lower down the topic from me. I forgot that I posted this.
Last edited by Beacons! on Thu May 29, 2008 8:04 pm UTC, edited 1 time in total.
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Re: Opinions/problems on a "force field"

Postby Zeltrix » Thu May 29, 2008 4:26 pm UTC

You could make it a spherical grid of extraordinarily small one ohm resistors that you run the charge through, so that any partical with less resistance than the points of the grid that it's close enough to for the electricty to arc would get zapped, but it would need an amount of electricty that boggles the mind to even begin to work. Unless I'm entirely wrong and need to shut up.
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watch_wait_plot
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Re: Opinions/problems on a "force field"

Postby watch_wait_plot » Thu May 29, 2008 4:34 pm UTC

Which is essentially the original problem restated.

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Re: Opinions/problems on a "force field"

Postby Beacons! » Thu May 29, 2008 8:02 pm UTC

I recommend reading Michio Kaku's latest book "Physics of the Impossible" on this matter. There, he (amongst other coolness) outlines what would be required of a stereotypical forcefield and how to meet such aims. It seems to involve a number of layers.

-A Carbon-nanotube mesh to keep out small to mid-sized objects
-A plasma wall controlled by an electromagnetic field to keep out any vacuum
-A curtain of lasers for your desired vaporisation effect
-A final layer of very advanced photochromatics to keep out lasers

Before you ask, photochromatics are the same technology found in those spectacles that darken when they enter sunlight. Despite the fact that modern ones only darken in response to UV rays, they could potentially be developed to block out other types of radiation.

All that and it would still stay invisible for the most part. No idea of the energy requirements, however.
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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Thu Jun 26, 2008 1:40 am UTC

Resurrected! I had another idea. http://www.youtube.com/watch?v=iABmUEH5 ... re=related

What else does this work on? If you cover something in huge electromagnets of Doom, then shoot stuff at it, can it slow it all down?

Of course, It cant totally stop it, but bullets etc wouldn't work so well. I'm also guessing this only works well on metals (not ferromagnetic obviously).
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Charlie!
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Re: Opinions/problems on a "force field"

Postby Charlie! » Thu Jun 26, 2008 2:29 am UTC

For eddy currents to slow stuff down, the stuff has to be conductive. So the first, say, quartz meteorite (or laser) you encounter will go right trough, even if you fulfill the mind-boggling energy requirements.
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Re: Opinions/problems on a "force field"

Postby hideki101 » Thu Jun 26, 2008 5:37 am UTC

http://en.wikipedia.org/wiki/Plasma_window

I guess this is somewhat like a forcefield...but actually it really is more like a magcon field from Star Wars: it seems you'll need to contain it.
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Re: Opinions/problems on a "force field"

Postby RAPTORATTACK!!! » Thu Jun 26, 2008 10:49 pm UTC

well the magnet would work on all matter right? everything conducts to some extent. Not lasers though.

I've seen plasma windows on wikipedia before, And it looked really cool. But don't you need magnets on both sides do contain the plasma? Or is there a neat trick I haven't thought of?
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Charlie!
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Re: Opinions/problems on a "force field"

Postby Charlie! » Fri Jun 27, 2008 2:43 am UTC

RAPTORATTACK!!! wrote:well the magnet would work on all matter right? everything conducts to some extent. Not lasers though.

You're not going to get quartz to slow down with eddy currents. You'd have lots of bad consequences first.

Using magnetically contained plasma sounds cool. Probably wouldn't be viscous enough at all though.
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