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Comment Not that simple (Score 1) 274

You are making a LOT of assumptions. All of these matter: Ability of the mirror to dissipate energy prior to ablation or meaningful distortion. Collimation of the beam. Reflectivity of the mirror at the laser frequency. Ability of the laser to stay on target, and for how long. Distance from the laser. Atmospheric clarity and particulate density. Atmospheric turbulence. Disruption from atmospheric heating.

It's just not as simple as you paint it.

Comment Re:how much it took (Score 1) 274

CIWS targeting is, as the acronym hints, "close in." You should think of the distance between the shooter (of anything) and the target as a lever. A tiny pivot at one end of the lever (the weapon's aim) translates to a "much" larger motion at the end of the lever (the point of impact.) Tolerances that will work at 100 yards aren't anywhere near close enough to work at many miles, or hundreds of miles in the case of missiles not aimed particularly at you (so you can be sure they will get close enough to hit.)

Comment Suitable defensive grid? (Score 1) 274

There are other issues. That truck was relatively close, between 1 and 2 miles ("more than a mile away"). To hit an ICBM at apogee, even it it goes right over you, you are going to have to spend a lot of energy on atmospheric heating, and you'll lose even more to atmospheric distortion. We're talking 300 to 700 times the distance, depending on exactly what "more than a mile away" actually means. But it is certain that 30 kw at the source will not equate to 30 kw at the target at those distances. So now the problem becomes more than "hit the target", it is also "stay on target for X time", and that assumes that enough energy can be delivered to overcome the missile skin's ability to dissipate it. Because if you can't do all those things, you can't hurt the missile.

Also, the odds of it going right over you kind of suck.

Comment Re: how much it took (Score 2) 274

I"m pretty sure a regular mirror would not be employed.

But here's some hand-wavy math.

If a mirror reflects 99% of the light that hits it at the laser frequency (remember, there's only one frequency to be covered), and the light that hits it can heat proportional to 30 kw (however one figures that), then the mirror is absorbing a 300 watt equivalent and reflecting the rest unless the reflective surface fails.

If the reflective surface is highly heat conductive and the beam isn't all that tightly collimated, likely it won't flinch at all. Like any impact, the effect is all about how much energy you can shoehorn into the smallest possible area. If the beam is ~1/3 of an inch on target, then given 99% reflectivity, it's effectively 1 kw / square inch. If the beam is 1/30th of a square inch on target, it's 30 kw/square inch absorption after reflection. So it makes quite a difference. I think.

Anyone who works with lasers and mirrors, feel free to step in and correct or expand.

Comment ...with remaining eye (Score 1) 274

1) is if the laser is in visible light or not. If you can't see the red dot source a mile off, you can't evade it.

Pretty sure if you "see the red dot a mile off", the location where your eye was is just the steaming, goo-surrounded beginning of a well-cauterized hole that completely transits your head. Assuming tight collimation. With a broader 30 kw beam, your head would explode (steam pressure), and with a really broad beam, you'd turn into a human crisp before you had time to think "Hey! Las..."

Comment Re:The gun fetishists and ammosexuals think (Score 1) 367

On the other hand, it's been commonplace to carry your gun everywhere in some places. The entire planet is not a concrete jungle in the style of Coruscant quite yet.

Taking your gun to school is only seen as a problem because some people choose to act hysterically when it comes to a particular bit of modern technology. They wallow in their fear and ignorance and take great pride in it. They confuse ignorance with sophistication.

It's seen as "something that's not done" simply because it's taboo and there's a good part of the population that chooses to be intolerant.

Comment Re:For regulation to work... (Score 4, Interesting) 367

Texas does in fact allow open carry of long guns. What it doesn't allow is open carry of hand guns.

In fact back when the whole Ferguson thing was more of a thing, there was an open carry demonstration by a black shooting club. They marched through one of our large cities (with rifles and shotguns) and deposited themselves next to a number of on duty police officers on their meal break.

No fireworks ensued though. Nobody got over excited. Although it does bear mentioning that the jurisdiction in question does have a black police chief and had a black DA.

Comment Re:Reader (Score 4, Interesting) 150

Too bad you didn't step up to the plate and become the maintainer, when Google offered to give the source code away to anyone who wanted to run their own "Google Reader" service.

It is not a problem of code, it is a problem of providing the service

When Google originally offered the code, they offered to host it on Google's hosted infrastructure service for a year, at no charge, until the project got up on its feet. There were no takers.

This will probably be moderated down as well... however, yes, "providing the service" is *exactly* the problem, and it's *exactly* why Google cancelled the thing when the back end hosting infrastructure APIs changed out from under the (unmaintained) Reader codebase. The maintainers had moved onto other projects.

And while Google could have either brought them back (the ones who wanted to revisit their old code), or they could have put new hires on the porting problem, and gotten Reader back on its feet on the new hosting infrastructure, it wouldn't have solved the basic problem.

The basic problem is that there was no sustainable revenue model for the service. Google's Reader service allowed the use of any client that someone cared to write, and a heck of a lot of people wanted to write clients that excluded advertising as a means of supporting the costs of running the service. Which would be fine, if there were any way to charge for it, *other* than advertising, which didn't break the client/back-end-service model, which is what people *liked most* about Reader in the first place.

So Google didn't throw good money after bad, and no one else stepped up to throw good money after bad, and (possibly) figure out some other way to monetize the service, such as changing the over the wire representation such that advertising was indistinguishable from content. Which wouldn't have worked, since that would just trigger an arms race for clever advertising exclusionary filtering in the display services, instead of at the protocol level.

So you're right: "it is a problem of providing the service", and the specific problem is "no one wanted to pay to do that".

Government

Video Come and Take It, Texas Gun Enthusiasts (Video) 367

In Texas, guns are a common sight:gun-racks are visible in the back of many pick-ups, and pistols, cannons, and rifles are part of the state's iconography. Out-of-sight guns are common, too: The state has had legal (though highly regulated) concealed carry for handguns since 1995, though -- contrary to some people's guess, and with some exceptions -- open carry of handguns is not generally legal. One thing that's definitely not a common sight, though, is a group of people manufacturing guns just outside the south gates of the Texas capitol building. But that's just what you would have encountered a few weeks ago, when an organization called CATI (Come and Take It) Texas set up a tent that served as a tech demo as much as an act of social provocation. CATI had on hand one of the same Ghost Gunner CNC mills that FedEx now balks at shipping, and spent hours showing all comers how a "gun" (in the eyes of regulators, at least) can be quickly shaped from a piece of aluminum the ATF classifies as just a piece of aluminum. They came prepared to operate off-grid, and CATI Texas president Murdoch Pizgatti showed for my camera that the Ghost Gunner works just fine operating from a few big batteries -- no mains power required. (They ran the mill at a slower speed, though, to conserve juice.)

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