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The Zap Gun
September 11, 2010 11:33 PM   Subscribe

Why we don't have laser pistols.
posted by Artw (64 comments total) 5 users marked this as a favorite

 
So, fledgling evil overlords take heart, laser guns may not be possible or practical...

Yes, but, I can feel like an evil overlord when I play with my laser pointer. Although, when I make it "disappear" under the couch, my cats are probably plotting various ways to take it away from me and torture me with it, if only they had opposable thumbs.
posted by amyms at 11:45 PM on September 11, 2010


Wait, nanobot bullets which aim for the genome of the target are more realistic than laser pistols?
posted by honest knave at 11:48 PM on September 11, 2010 [9 favorites]


The laser energy heats the target until it ruptures the fuel tank, or heats the explosive to its ignition temperature and boom! There goes the Death Star.

C'mon man, the Death Star was destroyed by proton torpedoes, not lasers.
posted by nathancaswell at 11:54 PM on September 11, 2010 [7 favorites]


Bottom line, however? Lasers just aren’t cut out for killing people.

Seriously, they tried that on Akira and Tetsuo and those kids just laughed it off.
posted by Blazecock Pileon at 11:54 PM on September 11, 2010 [5 favorites]


Please keep me advised about laser armament progress. I will just rely on good old bullets for now.
posted by Cranberry at 11:58 PM on September 11, 2010


But of course a really “Brilliant Bullet” wouldn’t even require a gun. It could be made larger, the size of a ball-point pen, say, with lightweight wings and a tiny engine that would push it silently through the air.

Hunter Seeker with face recognition?
posted by nathancaswell at 12:01 AM on September 12, 2010 [4 favorites]


Pssh! Like we didn't already know this. I played Traveller-- sandcasters and reflec armor TOTALLY showed the futility of laser weapons. Needle Guns, on the other hand . . .
posted by KingEdRa at 12:03 AM on September 12, 2010 [4 favorites]


Lasers just aren’t cut out for killing people.

They are when they blind airline pilots.
posted by bwg at 12:04 AM on September 12, 2010 [2 favorites]


This is not a good article - because he doesn't in fact prove his point at all. His model of the body is very poor - he treats it as if it's the same as water with respect to a laser, which is hardly true in any fashion - and he doesn't go into the details at all.

Who knows how your laser gun could be put together?

50kJ is the energy you'd get from converting about one two-billionth of a gram of matter into energy. If you wanted to be able to burn a hole in a body in a second, a gram of antimatter reacting with a gram of matter would last you over 100 years running continuously at 50kW.

Now, I'm assuming 100% efficiency of your matter-antimatter reaction and the subsequent conversion into lased light. But you'd better be hoping for pretty damn close to 100% efficiency... because otherwise you've going to get a rude surprise. If even 1% of that heat energy is waste, you're going to get 500 watts of heat right in your hand and you aren't going to enjoy it.

Actually, I suppose 500 watts of waste energy would be at about the limit that you could tolerate - you can imagine an aerogel handle that would insulate for hours. Perhaps if you had a serious fan of some type, too....

You could go much further than this article. If it weren't late, I would do it myself...
posted by lupus_yonderboy at 12:12 AM on September 12, 2010 [10 favorites]


Laser pistols may be impractical, but pain rays are well on the way to horrifying reality. Why kill the enemy when you can incapacitate?
posted by Rhaomi at 12:15 AM on September 12, 2010 [1 favorite]


I'm confident that humans will develop some kind of plasma burst rifle that will maim and destroy living creatures every bit, if not more, as thoroughly as metal projectiles propelled by rapidly expanding hot gasses. And it will make an appropriate "psscheeeew" or "wizzzsssschk" sound while doing so. Humans will find a way.
posted by Burhanistan at 12:17 AM on September 12, 2010 [4 favorites]


I read a really old story where the arm of the day was a pulsed laser. If I recall correctly, the secret sauce was some way to resonate a megawatt-range continuous-wave chemical laser to get very brief pulses. Each 'shot' consumed a small cartridge of chemicals and ejected a little plume of steam to carry of the waste heat. The story was very thorough about envisioning how this would affect tactics (lots of smoke grenades, reflective clothing underneath ablative camouflage paint, &c.) but unfortunately it had no plot that I recall.
posted by d. z. wang at 12:39 AM on September 12, 2010


Well. Yeah.

But what about phasers?
posted by utsutsu at 12:40 AM on September 12, 2010 [1 favorite]


If you'e got antimatter in a form you can control, why not just send it on its way to lodge inside the body of the enemy before losing its container?
posted by maxwelton at 1:23 AM on September 12, 2010


People, however, are much bigger, and usually try to get out of the way if they feel parts of themselves burning.

PESKY HU-MONS. YOU SHOULD HOLD STILL MORE.

and, bango, good night Seattle.

OH CRAP THEY'RE ON TO ME AGAIN, AND I JUST REMODELED THE VOLCANO. FIGURES.
posted by loquacious at 1:26 AM on September 12, 2010 [1 favorite]


If I recall correctly, the secret sauce was some way to resonate a megawatt-range continuous-wave chemical laser to get very brief pulses.

Good news! The US Military has built one.
posted by ryanrs at 1:38 AM on September 12, 2010


Vernor Vinge talked about a form of this idea.... his medium-future short stories had a small rebel group of tinkers in insurrection against a global authority of some kind, and he posited that technology advancements would make a small force of that type quite viable against a monolithic entity. One of his throwaway ideas was 'smart bullets', guns that fired in a stuttery, slow way, but which hit every single time. Poke your 'smartgun' around the corner, pull the trigger, and an entire enemy squad falls over dead.

50kJ is the energy you'd get from converting about one two-billionth of a gram of matter into energy

This is true, but the big problem with matter-antimatter reactions is that they throw off a crapload of gamma radiation, which can't be blocked or shielded, only attenuated, at least by any technology we're aware of. This might be usable in spaceships, but you'd have to have very long hulls to move the reaction chamber as far from living crew as possible, and they'd still get a pretty good radiation dose.

Even if we could develop a handheld antimatter reaction chamber, you'd be cooking yourself just about as fast as your target. You'd probably have to use a robot and telepresence to wield that kind of weapon, with the power plant being most of the robot.

Even if everything worked perfectly, it's going to be vastly more expensive than just throwing metal at the bad guys. Lots and lots that could go wrong with the laser solution, not the least of which is the possibility of the enemy disabling your robot and stealing your antimatter power cell. That would, I suspect, be bad.
posted by Malor at 1:39 AM on September 12, 2010


Well then somebody explain why laser cats are so damn effective!
posted by hal_c_on at 1:59 AM on September 12, 2010 [2 favorites]


Yes, but, I can feel like an evil overlord when I play with my laser pointer.

As a first-year undergraduate I took a course in modern European history. Some of it was taught by a distinguished historian of 20th-century France, a lovely gentleman who was near to retirement. At one point in the middle of a lecture on the 1920s, he interrupted himself while using the laser pointer to indicate Weimar on a very large wall-map of Europe and said--

"You know, these things give you a sense of enormous power. Ah-ha-ha--ve vill disstroy London!"

Then without a pause he went back to telling us about German Expressionist cinema, while in the background distant cries rose over London's smouldering remains.
posted by lapsangsouchong at 2:05 AM on September 12, 2010 [22 favorites]


Who needs laser guns, I want my laser whiskeys!
posted by benzenedream at 2:18 AM on September 12, 2010 [2 favorites]


If you could heat a gram of water to vapor quickly enough, the explosion would be sufficient to kill a person. So there's no need for a laser to drill a hole through him.

It takes about 2,500 joules to boil a gram of water at body temperature. That's 1/20th the 50,000 joules the article claims would be needed. Still a difficult number to hit in a handheld weapon.
posted by Jimmy Havok at 2:29 AM on September 12, 2010


Plus, on top of that, you've got the energy generation and antimatter storage problems to solve, as well.

You can't just find antimatter, you have to make it. At least at the moment, this is very, very difficult, and takes huge particle accelerators and ridiculous amount of power to make the tiniest amounts.

What they do is set up a chamber that will produce anti-protons, beaming a massive stream of particles into some reagent in the chamber. Anti-protons are produced, but nearly all of them are wasted, going off in random directions. A very few of them are emitted in the correct direction. They're magnetically guided into a track where they're cooled gradually to very near absolute zero, and then captured in magnetic containment. This whole process is incredibly inefficient. It takes something like a million units of input power to end up with one unit of stored power. So that means that your 50kJ pulse of power originally required something on the order of 50 million kJ to create. (!)

The containment can actually be pretty small, as we can make strong static magnets, and antiprotons near 0K have almost no energy. You could fit a couple grams into a handheld storage cube. The energy density is incredible. But you have two big problems... the cube has to stay very, very near absolute zero, and it can't be breached. If it warms up, or if, say, a bullet penetrates it, you will get an earth-shattering kaboom.

This could potentially work in spacecraft. There was an SF author awhile ago (maybe David Brin?) who observed that you could build rockets that used a trickle of antimatter into a standard engine to give it a huge output boost. You could use the same amount of matter propellant to go to the Moon or to go to Pluto... what would change would be the amount of antimatter that was added. And if you could run the rocket continuously, you could get essentially anywhere in the Solar System within a couple of weeks. For nearby targets, the rocket would use just a little antimatter and wouldn't accelerate that hard; for distant ones, it would use a lot and would accelerate like crazy.

But being able to use it in that kind of fairly controlled environment isn't at all like trying to use it in a combat vehicle. The energy density is so enormous that when a sufficiently powerful slug penetrated the storage unit, or if the vehicle crashed, or if the cooling system simply failed, you'd end up with a devastatingly powerful explosion. One feature you really don't want in military craft is fragility, so it's quite likely that antimatter power sources will never be used in any kind of front-line conventional conflict. At most, you'd have them in deep-standoff units that were hammering a battlefield from miles away. Or it might potentially be used in space, where distances are vast, and there's no Earth to shatter with your potential kaboom.

I think it's fairly safe to say that man-portable battlefield weapons powered by antimatter will never be feasible. If we want laser pistols, we'll need some other way to store the energy.
posted by Malor at 2:32 AM on September 12, 2010


Man, science ruins everything.
posted by Ghidorah at 2:33 AM on September 12, 2010 [4 favorites]


I'll give you my blaster when you take it from my cold, dead hands
posted by fearfulsymmetry at 2:51 AM on September 12, 2010


I'll give you my blaster when you take it from my cold, dead hands hot, irradiated, skeleton-fingers.
posted by No-sword at 3:33 AM on September 12, 2010 [6 favorites]


I seem to recall a laser-taser kind of dealie. The laser clears a path for the taser charge to travel, eliminating the need for wires. Pretty slick.

If projecting violence really matters though, chemically powered guns are the one true way and will be for a looooong time.
posted by codswallop at 4:23 AM on September 12, 2010


Apparently a laser sidearm would only need about 1,000 joules to incapacitate a human target, if you pulse the beam.
Laser Sidearms
posted by Nyrath at 4:33 AM on September 12, 2010 [2 favorites]


I created the giant death ray to help mankind, not destroy it!
posted by robocop is bleeding at 5:14 AM on September 12, 2010 [3 favorites]


Why we don't have laser pistols.

*takes off human skin, stretches tentacles, plops body into antigravity chair*

What do you mean by "we", Earth monkey?
posted by nomadicink at 5:14 AM on September 12, 2010


Laser pistols...fuck that noise. I want to know where my damn jet-pack is?!
posted by Fizz at 5:30 AM on September 12, 2010 [1 favorite]


I enjoyed the sober (if inadequate) science until the author launched into the modern equivalent of 1960s laser hype: Metamaterials as an invisibility cloak is pretty firmly misunderstood; by their nature, they're virtually impossible to make even remotely broadband, meaning they're only invisible if you only see in a single "color."
posted by JMOZ at 5:32 AM on September 12, 2010


I seem to recall a laser-taser kind of dealie.

Probably the electrolaser which uses a laser-induced plasma channel. The video is of an area defense application but apparently a couple of companies are working on hand held models.
From the wiki:
A Laser-Induced Plasma Channel (LIPC) is formed by the following process:
* A laser (possibly a laser diode) emits a laser beam into the air.
* The laser beam causes ionization of atmospheric gases to form a plasma.
* The plasma forms an electrically conductive plasma channel.
* A fraction of a second later, a powerful electric current is sent down this plasma channel.
* Foul odors ensue.


Oh yeah, and the dude, or chick named Jeff that wrote the article is, by the end, straight buzzword metananotrippin.
posted by vapidave at 5:44 AM on September 12, 2010 [2 favorites]


Even if you fix the science, there's still good reasons not to invent laser pistols or rifles. Range, for one thing. One of the good things about weapons that fire large lumps of lead is that if you miss the target - or even deliberately miss, if you're laying down suppressive fire - the bullet's going to come to earth before too long and probably not kill someone three miles away (although that very thing has been known to happen). If you have a very powerful, very focused laser weapon, though, that's not going to lose a lot of energy just going through the air, and you do stand a fairly good chance of boring a hole clean through the civilian minding his own business (or maybe one of your allies) in the next town over.

Probably less of an issue in an aircraft which is firing downwards, or in something vehicle-mounted which can be carefully aimed, but that's not the kind of power I'd want in an infantryman's hands.
posted by ZsigE at 6:06 AM on September 12, 2010


*takes off human skin, stretches tentacles, plops body into antigravity chair*

Sorry, but I keep reading that as "testicles."
posted by GenjiandProust at 6:06 AM on September 12, 2010 [1 favorite]


Pssh! Like we didn't already know this. I played Traveller-- sandcasters and reflec armor TOTALLY showed the futility of laser weapons. Needle Guns, on the other hand . . .

Yeah, I was gonna say: one of the criticisms of Traveller was that there was not enough in the way of energy weapons, and that even 3700 years hence, opposing forces were still firing bullets at each other. Looks like Marc Miller was right on this one.

The weights of computers, on the other hand...
posted by ricochet biscuit at 6:07 AM on September 12, 2010 [2 favorites]


GenjiandProust: "*takes off human skin, stretches tentacles, plops body into antigravity chair*

Sorry, but I keep reading that as "testicles."
"

That's why you'd need the antigravity chair.
posted by bwg at 6:09 AM on September 12, 2010 [2 favorites]


By the 1920s a few of them, notably Nikola Tesla in the U.S. [...] made the somewhat dubious claim that, indeed, a death ray could be built.

[...] but top scientists certainly didn’t, and after World War II, a high-level review panel proclaimed death rays to be an impossibility.

And unfortunately, the killjoys were right.


Sorry. If Nikola Tesla said it could be done, I believe it.
posted by Malice at 6:19 AM on September 12, 2010 [6 favorites]


The correct way to weaponize a laser is to drop it in a sock and hit someone over the head with it.

Plus: no "you'll put your eye out jokes?". Sigh.
posted by eriko at 6:33 AM on September 12, 2010


Never-mind the problems with "laser pistol" - what about the problems with "pistol": first of all you have to get into close contact with the person that you want to kill and hence you put yourself at risk. Secondly, if you do end up killing the other person you run into all sorts of legal and ethical problems - plus you have to dispose of the body and clean up the mess.

It would be far better to have a personal drone which would track down anybody problematic well before they got near you. It would then offer them a choice such as 1) Convert to your cause, 2) Receive a general Brainwashing 3)Complete, but relatively pain free, vaporisation leaving no messy stains. The first option is the most eco-friendly as any zombie will tell you.
posted by rongorongo at 6:58 AM on September 12, 2010


Betting on science not being able to do something is like playing pool against a guy named after a state. You may be right now, but it won't last forever.
posted by Etrigan at 6:59 AM on September 12, 2010 [1 favorite]


"It is possible to synthesize excited bromide in an argon matrix."
posted by eric1halfb at 7:02 AM on September 12, 2010 [3 favorites]


If you have a very powerful, very focused laser weapon, though, that's not going to lose a lot of energy just going through the air

I was thinking the exact opposite -- from the perspective of the photons there's no difference between water molecules in the atmosphere and water molecules at the target. It's often brought up as a stumbling block for why military lasers are not yet practical for ground-based warfare (such as p11 of this report). Sure, the density of stuff in the atmosphere is a lot less than that density of the target, but the distance that the beam has to travel magnifies that effect. That article mentions that adaptive optics are needed for targeting due to the scattering by particles in the air, which to me makes it sound like something that would rule out hand-held versions.
posted by Rhomboid at 7:10 AM on September 12, 2010


I far more prefer the disintegrator idea over some heat-ray laser weapon. An energy weapon that destabilizes the atomic bonds of the target, causing it to literally fly apart and dissipate suddenly.

I can be reached at my secret castle fortress if you have any questions.
posted by Thorzdad at 7:11 AM on September 12, 2010


I like the way he starts by making fun of the credulity of science writers from last century regarding lasers, and ends up describing ball-point pen sized invisible cruise missiles that fly around searching out their targets using long-range DNA analysis.
posted by TedW at 7:27 AM on September 12, 2010 [3 favorites]


a shiny metal box about the size of six McMansion-sized refrigerators. Even Godzilla would have a hard time lifting that.

That is the least descriptive description I've ever read. So, is it the size of six refrigerators if refrigerators were the size of McMansions? How big is a McMansion? Or are the refrigerators of a size suitable for use in a McMansion? Either way, I think Godzilla could lift it easily enough.
posted by cmoj at 7:45 AM on September 12, 2010


Neal Stephenson's novel The Diamond Age is set in the late 21st century and the weapons of the time are all based on nanotechnology. While the novel isn't great, it's depiction of these weapons, in light of this article, are rather terrifying.
posted by Vindaloo at 7:55 AM on September 12, 2010


awwwwwwwwwww!

*pouts*
posted by liza at 8:10 AM on September 12, 2010


Because of the very very real threat of Lasercats?
posted by bitter-girl.com at 8:46 AM on September 12, 2010


Yeah, there are lots of Neat Things for which we haven't found the appropriate principles that would make them feasible-- AI, for example.

For such things, we're still in that stage of the process that can be compared to trying to fly by strapping big wooden planks to our arms and flapping our arms really hard.
posted by darth_tedious at 8:57 AM on September 12, 2010 [1 favorite]


How old is this article? Raytheon demonstrated a laser weapon with the capability to shoot down at least lightly-armored UAVs over the summer. Still doesn't solve the "need a ton of energy" problem, or the "really farking big hardware" problem, though, or the "mainly effective against things that heat up and explode" problem. And of course that was a PR stunt, with the odds stacked in the laser's favor, I'm sure.

Also, the description of the smart-bullets made me think of the knife missiles from Banks' Matter, among other things.
posted by Alterscape at 8:59 AM on September 12, 2010


Lasers schmasers. I wants me my orbital railgun!

It's the only way to be sure.
posted by zoogleplex at 10:06 AM on September 12, 2010


> Lasers schmasers. I wants me my orbital railgun!

I know a guy who lives in an old aircraft carrier converted into a small city will give you the plans to make one of those out of found junk if you give him a copy of the Declaration of Independence.
posted by Burhanistan at 10:26 AM on September 12, 2010 [1 favorite]


The key to making a laser do bullet levels of damage is pulsing the laser. The first pulse creates a steam explosion and a shallow crater in the skin of the hapless pirate. By careful timing, the second pulse arrives after the steam from the first pulse has dissipated and creates a second crater at the bottom of the first. If you don't delay the pulses, the cloud of steam interferes with laser beam, protecting the target. By altering the variables one can have a laser beam that will penetrate a human body but only bore a little way into metal. As an added bonus, lasers have no recoil.

ProjectRho.com's Atomic Rockets
posted by OldReliable at 10:38 AM on September 12, 2010


In the presence of certain forms of sealife, miniature lasers possibilize.
posted by mistersquid at 10:39 AM on September 12, 2010


Man, science ruins everything.

Ruins? They invented the freaking death ray, and then produced billions of them, for the primary purpose of playing music. The laser is one of the most hopeful stories to come out of the 20th century.
posted by roystgnr at 11:21 AM on September 12, 2010 [2 favorites]


Fuckin' laser pistols, how do why don't they work?

Laser pistols...fuck that noise. I want to know where my damn jet-pack is?!

Fuck jet-packs, where's my Moonbase? It's 2010 already and I was promised a Moonabse by 1999. I know I was, I had the lunchbox!
posted by Pirate-Bartender-Zombie-Monkey at 11:35 AM on September 12, 2010 [1 favorite]


That's why they call them "blasters" in sci-fi, and not "lasers". Lasers are great for scanning UPCs at the grocery store. Blasters are for killing scores of clumsy stormtroopers.
posted by Xoebe at 1:04 PM on September 12, 2010


Talk about stating the obvious. This article is about why current small lasers are not powerful enough to kill people, not why lasers are inherently nonlethal. "Lasers just aren’t cut out for killing people." Yeah, right. Once we miniaturize power sources they will work fine as man-portable weapons.
posted by mnemonic at 1:14 PM on September 12, 2010


mnemonic: "This article is about why current small lasers are not powerful enough to kill people [...]"

Yeah, what got me was this quote:
It also has never been operated outside the controlled environment of a laboratory, draws 500 kilowatts of electricity, and is rather inconveniently housed in a shiny metal box about the size of six McMansion-sized refrigerators.
ENIAC weighed 27 tons and took up 63 cubic meters of space, and nowadays I can get that calculating power in a 1x0.5x4 cm DIP package that weighs two grams.

I don't see laser weapons as generally impossible - even if we develop a more efficient way of generating / storing energy and they still turn out to be inefficient they will still have niche applications (sniper rifles that work at the speed of light, with no bullet drop or wind deviation; sealed solid-state weapons with no moving parts; soundless guns that cannot be tracked etc.). And there is always the possibility of synergy with other technologies: I always liked the idea of high-power electrical discharges along a path of ionized air molecules generated by an UV laser.
posted by PontifexPrimus at 1:30 PM on September 12, 2010


Actual laser weapons are boring anyway. Let me know when science shows us how to make the "laser" guns in Star Wars, that fire foot-long 'bolts' that are almost slow enough to dodge and can't really hit protagonists.
posted by graventy at 1:53 PM on September 12, 2010


"It is possible to synthesize excited bromide in an argon matrix."

Hmmm... interesting. Very high power, portable, limited firing time, unlimited range. All you'd need is a big spinning mirror and you could vaporize a human target from space.
posted by lefty lucky cat at 3:59 PM on September 12, 2010 [1 favorite]


Lasers might not make viable weapons in and of themselves, but I bet that if you could perfect using one to ionize the air between you and a target and then create a sufficiently powerful jolt of electricity to run along that path, you'd have something every bit as sci-fi as a ray-gun.

More so in fact, because "Lightning Gun" just perfectly embodies those old pulp serials.
posted by quin at 8:05 AM on September 13, 2010 [1 favorite]


GenjiandProust: "*takes off human skin, stretches tentacles, plops body into antigravity chair*"

"Sorry, but I keep reading that as 'testicles.'"

"He kept trying to put his testicles all over me!"

"His what?!"

"How you say...like octopus?"

"Ah! Tentacles. N-T. Very different."
posted by djwudi at 8:47 AM on September 13, 2010 [3 favorites]


TWO DOLLARS!
posted by KingEdRa at 6:59 PM on September 13, 2010


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