A knife cuts well because the edge is thin. A strong, extremely thin string would do the same thing.
That got me thinking. If we had a thin, carbon nanotube monofilament string, strong enough to not snap, yet thin enough to cut through something, you would have a handy weapon.
The problem is, it would be so hard to see and so easy to lose. Also, if you tried to use is, your fingers would get cut off. Therefore, you need a holder of some sort. Now, we could attach a handle to one end, but we need a counterweight at the other. Then, if the counterweight was a magnet, and the handle had an electromagnet that repelled the counterweight, the monofilament would stretch out really tight, like an invisible sword, except that you couldn't stab with it. You could put a spike on the counterweight, but that's beside the point.
Now, you add a roll-up mechanism inside so you can stow it away safely.
To use, you pull it out and flick a switch. The magnetic forces stiffen the wire making a useful "sword" that is hard to see.-- DesertFox, Aug 20 2004 Carbon Nanotube Cheese Slicer http://www.findarti...25_170/ai_n17114212For very, very small, very thin, slices of cheese. (Actually, frozen cells.) They're still working on getting the spot-welds between the two tungsten tips to hold, though. [jutta, Mar 21 2007] Another method: Keep handle and blade concept, but insead of magnet just use a weight. Then you can whip the thing around for a completely new weapon technique. Or, create a holder like a violin bow.-- Worldgineer, Aug 20 2004 What's it made out of? Most substances I can think of would snap if they were that thin. The other ones I made up. A good tool for assassins if it could be made.-- harderthanjesus, Aug 20 2004 I'm fer it. Grab the spike and hold the handle while disabling the magentics and it's a very messy garrotte. I think I'm going to have to look through this cattegory...-- Ichthus, Aug 20 2004 I didn't mention the swinging counterweight option? I swore that I put it in. I must have forgotten.-- DesertFox, Aug 20 2004 The swinging counter weight option sounds dangerous to me, definite potential for cutting your own head off.-- scubadooper, Aug 20 2004 A similar weapon is described in the William Gibson short story and screenplay "Johnny Mnemonic," but the filament is flexible and the weight is swung in a circle to create a lethal 'disk.'-- bpilot, Aug 20 2004 Contracts, the wedge is there because the blade has to get thicker or it will snap. Also to force the object you are cutting apart. You just need it to be thin enough to pass through the object you are cutting. To be sure, we could make the monofilament triangular.
harderthanjesus, read the second paragraph. Carbon nanotubes are really strong. They talked about using them to build a space elevator. These carbon nanotubes would probably be more than strong enough.-- DesertFox, Aug 20 2004 Surely an electromagnet strong enough to hold a nanotube into a sword will probably be strong enough to do you a fair bit of damage/pull in nearby cars/ require to you to carry around a small city to power it.
I'd stick to the counterweighted monofilament hidden beneath the false thumb, but that was baked in SF a long time ago.-- st3f, Aug 20 2004 So far (to my knowledge) they've only been able to make nanotubes of a few mm in length, that could be a slight problem if you want to slice and dice anything other than a nematode or two-- scubadooper, Aug 20 2004 With a stiff filament, one could bend it in a bow back to the handle and use it in two directions, slicing and lopping.-- FarmerJohn, Aug 20 2004 This would probably be best as a whip.-- 2 fries shy of a happy meal, Aug 20 2004 //require to you to carry around a small city to power it//
So does a laser. If it were possible (I'm no laser tech) to put a reflector at the end of a bow and aim it straight back into the lasing medium, some of your energy would be conserved by not having to pump the lasing medium as much. It would also provide a finite laser length. Most of your energy losses would be at the reflector, so it would have to be kept clean and chilled. Depending on how little energy losses there are, you might only need a small amount of power to keep it going, but a capacitor for the initial fire.
But, in regards to lasers, I don't know enough to know that I dont know anything about them.-- destructionism, Aug 20 2004 I could slice huge chunks of cheese with one of these.-- skinflaps, Aug 20 2004 [contracts] Let me guess, this is how George Lucas describes how his lightsabers work?-- destructionism, Aug 20 2004 You have described a standard niven weapon, the "variable-sword". The extreme strength and rigidity of his blade are explained by a "stasis field" around a monofilament chain of large molecules.
Ouch.-- GutPunchLullabies, Aug 20 2004 [contracts] If I have access to lasers, safety equipment, and piles of money, I'll tell you if it works.-- destructionism, Aug 20 2004 Well it seems GPL has beaten me to the punch. Yep, halfbaked by Larry Niven. I suppose that earns this idea a [wibni].-- Freefall, Aug 20 2004 I think that the sword could function more than well, if it had a supportive structure, eg. from polymers, ceramic material mixed with polymers (ideal cos ofit's endurance and hardness) or metal. A metallic sword that is naturally magnetic and possibly ferromgnetic, could face severe problems: It would become a weapon against it's user if the enemy gains control over local magnetic fields (portable inductor, powergrid, etc) So we'd have to develop the sword as magneticallly neutral as possible. Then you could even stab with it through armoured plates.-- fishdish, Aug 20 2004 Yes, this is Larry Niven's variable sword. GPL beat me to it, too. But anyway, does not a sword need some mass too?. A mandoble was very heavy. Imagine one of those made out of today's materials, as fishdish says, and then covered with diamond-like carbon. Will that cut, man ! . On the other hand, so will a diamond covered katana. Does somebody have a spare stasis field somewhere?.-- finflazo, Aug 20 2004 what [bpilot] and [st3f] said, about it being concealed in the weighted prosthetic tip of a bodyguard's thumb. Talking of Gibsonesque weaponry, in Neuromancer, what exactly was a Cobra? Sounded pretty nasty, but I could never properly picture it in my mind.-- zen_tom, Aug 20 2004 You'd get cancer if it snapped and you accidentally inhaled it.-- mailtosalonga, Aug 20 2004 Also halfbaked by William Gibson, IIRC. Some ninja type slipped off the tip of his (prosthetic) thumb, leaving it to dangle on the end of this filament, which was attached to the base of where his thumb used to be. He summarily sliced a fat man neatly, and let his parts slide to the floor, a la anime.-- absterge, Aug 20 2004 random, halfbakery