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Warfare at the Speed of Light
unassimilatible writes "From the They Said It Couldn't Be Done Dept., the Oakland Tribune reports that the Lawrence Livermore Labratory is ensuring that the Pentagon, inside of a decade, could be armed with a beam weapon that is near-instantaneous, gravity-free and truly surgical, focusing to such hair-splitting accuracy that it could avoid civilians while predetonating munitions miles away - perhaps someday even being mounted on Humvees."
Laaaaaaaaaaaaaaaaaaaaaser
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Kent, Stop playing with yourself.
"The ignorant fight to win, the wise win before they fight." -Sun Tzu
Hold Your Fire!
Too Late!
You Vaporized Kenny! You Bastard!
can you point it at a mildly victorian house from on board a jet fighter and fill the house with popcorn?
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
The evoloution of Thinkgeek's line of optical toys: 1. Red Lasar 2. Green Lasar 3. Lasar capable of pre-detonating munitions from miles away. (But no one will buy it because it is neither green nor capable of being seen in the air.)
"We're anxious to get out there and do something."
Always reassuring when someone in the US Army makes such a statement...
A laser arms race already is under way, chiefly in California.
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Wow, Goverminator hasn't been elected for 2 weeks and Skynet is already flexing its muscles
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
It's pretty funny that in the 50's, SF writers thought we'd have weapons like this and things such as moon bases by about 1980, but they also that there would be superpowerful computers...with vacuum tubes.
Leaving aside the technical issues of "can you do it," there are the political and moral issues of "should you do it." Precision guided, 100% accuracy is fine until you target the wrong point. The notion that we can have zero collateral damage assumes that we can distinguish between combatants vs. innocents and allies with high accuracy.
This invention might lower the tragedies of war if we have the intell to discriminate accurately. It might also increase collateral damage/friendly fire if the device inspires overconfidence in those who press the trigger.
Two wrongs don't make a right, but three lefts do.
Conspiracy theorests trade tin-foil hats for head-mounted mirrors.
The bold print giveth, and the fine print taketh away
And yet it can't be used defensively?
How about the following quotes?
"What we're building... Is a laser for cutting through mountians (roads, mines etc.)"
"What we're building... is a laser to defend our skies, country against missles"
"What we're building... is a laser to cut underground bunkers on the moon"
"What we're building... a giant popcorn popper"
This is kind of sad, when we just exploit technology with weapons in the forefront of our minds and not research or domestic uses! I mean I know they're from the DoD, but with war on their minds, goodness knows what else they're up to.
But would the detonating munitions know to avoid civilians as well?
Would a gravity-free weapon (even with light) defy General Relativity?
Will the enemy start using mirrors?
"... it could avoid civilians while predetonating munitions miles away..."
So it can avoid civilians who are miles away from the munitions? Even the few dumb bombs dropped on Iraq avoided most citizens in Kuwait...
I think (that you know) that it means munitions miles away from the LASER could be predetonated (pre- as in before the enemy sends them our way).
But the real question here is how whether they're implying that the civilians could be detonated too, separately without the munitions, now that we'll have got a big friggin' laser gun...
Not really. That's like saying you can simply swat bullets away. There's too much energy in lasers for common mirrors to reflect--they simply melt. As I understand it, modern mirrors for targetting lasers are wicked things like nitrogen-cooled mercury, controlled by pizoelectrics.
Anyone who loves or hates any language, platform, or manufacturer, doesn't know what they're talking about.
International treaty forbids the use of lasers for blinding people. But there is no legal ban on striking humans
You know, if you take a laser pointer, and you point it at a fluffy poodle being walked by a little old lady at night, she might just get startled and scream a little bit. Not that I would know firsthand or anything...
--Lawrence Lessig for Congress!
Since we are nowhere near a black hole, the light beams are going to be virtually straight for all intents and purposes. The most a beam of light would ever travel across land is about 100 KM (to the horizon) or a few KM if shot at an airborne target. Given that light would typically travel 1/3000 to 1/1000 of a second (300,000KM/sec), and would only accelerate downward under the force of gravity at a maximum of approximately 10M/second, you are talking total vertical displacement of about 1.5 to 4 millimeters max. A relatively small laser beam could hit a bullet miles away without even bothering to correct for the gravitational effect.
I know this is meant to be a joke but the actual technology involved in deploying a battlefield laser is immense. Here in the lab we've been working on civilian grade laser weapons (obviously at much lower power than the military; they are purely non lethal) and there are several major obsticals.
The main problem is that any reflecting surface can act as a mirror, meaning that you are constantly at risk of the laser beam bouncing back and obliterating you. What is worse is that if the surface is concave and you are roughly a focal length away then the beam with become focussed upon you and will so be many times more powerful. You can overcome this by making your laser beam non monochromatic and out of phase, but the engineering challenges in doing this are immense.
In addition the power contained by a laser can be enough to break down the chemical bonds in many innocuous compounds to form toxins. We had one nasty incident where our laser hit a puddle of water and turned the h20 into h202 which is deadly hydrogen peroxide. This would not look good for the US government if it started turning enemy cities into poisonous wastegrounds with a supposedly surgical weapon.
All that glitters has a high refractive index.
Absent human intent and use, technology stays on the shelf. Getting on a moral high horse about new weaponry will not stop people from deciding to war on each other, It will only ensure that they use more primitivw weapons.
War won't diappear if we're afraid to use new tools. People will throw rocks at each other if they have nothing else.
-- Slashdot: When Public Access TV Says "No"
"No coherent plan" to use lasers in warfare?
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Wrong, the DOD already uses laser rangefinders, laser-guided bombs, ring-laser gyros in submarines
Most likely they mean use of lasers as weapons, and it would be nice if it stayed that way. The inventor of the laser was recently quoted as saying that in spite of seeming like a death ray, he was unaware of any instance in which a laser had directly killed anyone, even by accident.
Toronto-area transit rider? Rate your ride.
"There goes the supertechnological soldier, staggering forward to wreak destruction on anyone he can entice within range. Meanwhile, the despicable enemy has opened fire with an old-fashioned but extremely efficient sub-machine gun."
Wish I could remember who wrote that book.
Well one of the labs in the running is actually developing them for use in fusion, this is a side effect kinda thing, and the military paying for the weapon would help fund the research side of things. NOthing pushed forward technology like military spending
Whether we like it or not, the US spends as much on defense as the next 10-15 countries combined. Many R&D innovations start off as defense-related technologies and only later get applied to civilian problems. That's because our government is much more likely to fund research that has military uses. Other countries (e.g., Japan, Germany) are more likely to help corporations with their R&D project. Not the US.
GMD
watch this
Holds up a mirror?
What is stopping the "other side" from coating their shells with a reflective surface? Especially if only one particular wavelength is used by the military, it should be straightforward to create a coating that'll effectively reflect close to 100% of the LASER.
The simple answer is "dust". The laser has very high energy. It hits the mirrored surface. The dust on the surface absorbs a large amount of energy very quickly. It essentially explodes, pitting the mirror surface. At this point, your mirror isn't a mirror. Game over.
The same applies for absolutely anything that can stick to or affect the surface, like skin oil or tiny scratches. This ignores the fact that you can't make a 100% reflective mirror, so it's going to heat up, and if you have enough energy you disrupt it anyway. Even a tiny fraction of a percent of inefficiency will take you to the cleaners.
That said, never say never. In the foreseeable future, it isn't a practical solution, though.
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Except for the fact that they light up really nicely and make a great target for conventional bombs. So, pick how you want to get scratched...
You can tell a great deal about the character of a man by observing those who hate him.
When will we stop spending R&D money on weapons and start spending on disease control, and quality of LIFE programs? I know of a half million people with spinal cord injuries who would gladly forgo laser-based weaponry so they might forgo the use of a wheelchair. Does anyone have budgetary numbers reflecting the spending variances between medical and military R&D in the public sector / private sector?
Uh yeah, if you are shooting at something in the horsehead nebula that might be an issue, you tart! Unless some fuckhead coughs up a black hole in Bagdhad (in which case it really wouldn't matter if the weapon shot blue bananna peels and laughing Barneys for all of the few nanoseconds Earth manages to survive), I don't think there is going to be any problem pointing the weapon at a large object and hitting it. The amount of deviation might be a problem if they were trying to score hits against the tachyonic particles in Saddam's mustache, maybe.
That's because you are correlating timing between objects with different frames of reference.
2 things: relativity of simultaneity and moving targets
Any gravitational affects on the weapon beam would have affected the light coming from the target in the same fashion.
only if they are the same path (still object) and the same frequency (index of refraction is wavelength dependent)
A Usenet Troll Triumphs on Slashdot
The main problem is that any reflecting surface can act as a mirror, meaning that you are constantly at risk of the laser beam bouncing back and obliterating you.
I am guessing that "lasers of mass destruction" would operate in the ultraviolet. There aren't many materials that will reflect ultraviolet light back at you. At best it might glance off a mirror if it hits at a shallow enough angle.
:wq
you are constantly at risk of the laser beam bouncing back and obliterating you.
If you stand next to a solid surface, like a tank, and fire a conventional automatic weapon at it, you had better be wearing some serious bullet proof armor.
The main problem is that any reflecting surface can act as a mirror
Mirrors do a great job of reflecting low power light. Put a sufficiently high powered pulse laser on the scene, and the behavior of reflective surfaces becomes "non-linear" in the sense that it will simply burn through them.
and turned the h20 into h202 which is deadly hydrogen peroxide
Which is regularly used as a mouth wash, and easily noticeable because it tastes like crap and fizzes in your mouth.
From my internet research of high energy lasers, it appears that the longest range that a laser will have in the forseable future is 6 miles through the atmosphere. In space a laser can go forever, but in the air thermal blooming, atmostpheric turbulence and normal attenuation make it impossible to blast things farther.
Thermal blooming is a big problem. A laser heats up the atmosphere around it which causes the index of refraction of the air to change which changes the direction and focus of the beam. And this is a non-linear chaotic system. You can't aim a beam a long way through the atmosphere. So that mean you can't use laser beams to shoot down incoming missiles unless you station the laser really close to the targets. And even if you do that, you can only start shooting when the missile is within 6 miles or so of the target. And even then if its bad weather - no go.
Laser weapons have some fundamental physics problems to overcome. It would be good if the US goverment told the tax payers about this before spending tons of money on them.
As the general theory of relativty predicted (confirmed by numerous observations), even light is not free from the effects of the curvature of spacetime.
So this beam weapon can't be "gravity-free"!
This would actually be a legitimate application for "smoke and mirrors". The article did refer to problems with particulates.
My other car is a 1984 Nark Avenger.
That actually should be: This laser is capable of emmitting a beam of pure vaporware
If you don't like what I write don't be a CS and mod it down. Refute it.
Yea I can't spell. So what is your point?