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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."
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.
"No coherent plan" to use lasers in warfare?
...
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.
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.
The military is heavily funding research into what they call "total battlefield awareness" which can be thought of as identifing every object in the battlespace. I think the idea behind this article is that if that research goes well, and the laser research goes well then we might finally be able to drastically reduce civilian casualities.
A large part of the problem is that most of America's adversaries purposefully mix their military forces in with civilians to prevent us from firing upon them. The pinpoint accuracy that laser weapons could give us might be enough to prevent our enemimes from using their own population as human shields.
GMD
watch this
Correct me if I'm wrong, but isn't the weapon that the Battlecruisers use in StarCraft (humans) called a "Yamamoto Cannon"?
Oh, wait...it's a "Yamato Cannon". Fine, so I'm missing two letters.
Zodiac Survey
I wouldn't say it makes no sense; after all, a literal quantum leap is a discrete change of state, and thus contrasts with a continuous incremental change (drift). Schrdinger's Cat makes use of the idea (which, apparently, its author thought ridiculous) of a discrete change in quantum state that has a macroscopic upshot.
"Oh, I hope he doesn't give us halyatchkies," said Heinrich.
Nobody will ever read this because I'm late to the party, but... When I was in the Army, my battalion was deployed to secure Tuzla airfield as the first wave of the NATO force implementing the Bosnia peace accords. Part of that package was a couple of Q-36 "Firefinder" radars, which were supposed to detect incoming artillery rounds, provide early warning, and provide counterbattery targeting data to our artillery battery. Given that nobody felt the need to lob any artillery shells at us, it was amazing how many warnings we received - presumably from birds and other non-threatening objects (I was a rifle platoon leader, so I don't know the full scoop). Had we had such a laser on site, I imagine we'd have had a lot of roast birds around the perimeter. Further, the two radars we had, aside from servig as a massive radiation hazard to those of us wandering around, could only cover about 40% of the perimeter. All this to say that the above post has a point - we'll need far better detection and targeting equipment before the laser is useful for defense against incoming artillery. And we'll still need robust and redundant targeting procedures before the weapon can be employed in an offensive mode.
Would a gravity-free weapon (even with light) defy General Relativity?
Gravity is the curving of space-time and light travels through space-time - curved or not.
If space-time is curved, then light travels a curved path.
The entire near-instantaneous, gravity-free line is fluff. You can't send a beam faster than light and as long as the beam has momentum (which light does) then it will feel the effects of gravity..
Will the enemy start using mirrors?
It depends on the frequency. Regular mirrors work for visible light. Doing optics at other frequencies can be very tricky.
For instance, your see through microwave door is opaque to the microwaves.
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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"!
Levels of rotational energy are quantum levels.
taken! (by Davidleeroth) Thanks Bingo Foo!
Power falls off as a function of both distance (scattering effects because you can't focus light beyond collimation) and the reflectivity of the surface. In terms of the cutting ability, you're probably more used to a profiler that has a cutting distance of around 25mm from the surface.
Oddly Draconis
Too cynical to live, too stubborn to die.